JP4047606B2 - Air pump - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an air pump that sucks and exhausts gas using a diaphragm.
[0002]
[Prior art]
As a conventional air pump, as shown in FIG. 6, a diaphragm 52 that covers a through hole 51 formed in a pump case 50 and a drive motor 53 that deforms the diaphragm 52 are connected via an eccentric crank 54. Is known.
[0003]
The eccentric crank 54 is bent at a right angle through a bearing 54 a, one end 54 b is eccentrically attached to the rotation drive shaft 53 a of the drive motor 53, and the other end 54 c is concentric with the central portion of the diaphragm 52. It has been fixed.
[0004]
In this air pump, the diaphragm 52 is deformed by an eccentric crank 54 that is rotated by a drive motor 53, and the volume in the pump case 50 is changed. Gas is sucked into the pump case 50 when the volume is increased, and gas is discharged from the pump case 50 when the volume is reduced.
[0005]
[Problems to be solved by the invention]
However, in the above-described air pump, the axial direction of the drive motor 53 and the axial direction of the diaphragm 52 are orthogonal to each other, and the movement locus of the other end 54 c of the eccentric crank 54 is not along the axial direction of the diaphragm 52. Therefore, when viewed from the axial direction of the rotational drive shaft 54a of the drive motor 54, the other end portion 54c of the eccentric crank 54 oscillates in an 8-shape, and the diaphragm 52 is not deformed in the axial direction.
[0006]
In addition, large vibrations and noises are easily generated when the gas is sucked and exhausted, and the diaphragm 52 may be deteriorated at an early stage.
[0007]
Furthermore, since the axial direction of the drive motor 53 and the axial direction of the diaphragm 52 are orthogonal, it is difficult to reduce the size.
[0008]
Accordingly, an object of the present invention is to provide an air pump that suppresses vibrations and noises that occur during the intake and exhaust of gases, is less prone to early deterioration of the diaphragm, and can be downsized.
[0009]
[Means for Solving the Problems]
In order to solve the above-described problems, the present invention provides a cylindrical body disposed in a cam chamber and attached concentrically to the diaphragm at the center of the diaphragm, and rotatable in the cylindrical body and relatively movable in the axial direction. a rotary shaft which is immovably held rotatably and axially with the pump case is loosely fitted in, and a drive motor for rotating the rotary shaft around an axis provided, at the peripheral portion of the diaphragm pump chamber or An annular bulging protrusion projecting into the cam chamber is formed concentrically, and a wavy cam groove extending in the circumferential direction is provided on either the inner peripheral surface of the cylindrical body or the outer peripheral surface of the rotating shaft, and the other is is provided with a guide projection to be fitted in the cam groove together, the cam groove, the deformation stroke when the diaphragm is deformed toward the projecting direction of the annular swelling projection, the projecting direction of the diaphragm is annular swelling projection In the opposite direction It characterized in that it is shaped to be larger than deformation stroke when deformed I.
[0010]
According to the present invention, the deformation direction of the diaphragm can be smoothly deformed along the axial direction, and vibrations and noises generated during gas intake and exhaust can be suppressed, and the diaphragm is deteriorated. It becomes difficult.
[0011]
Furthermore, it is possible to reduce the size by arranging the diaphragm, the cylinder, the rotating shaft, and the drive motor concentrically.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described below with reference to the drawings showing embodiments.
[0013]
1 is an air pump. A pump case 2 of the air pump 1 is partitioned into a pump chamber 3 and a cam chamber 4 by a diaphragm 20.
[0014]
Further, the pump case 2 is formed with an intake chamber (intake port) 3a having an intake opening 5a communicating with outside air and an exhaust chamber (exhaust port) 3b having an exhaust opening 5b communicating with outside air.
[0015]
The intake chamber 3a and the exhaust chamber 3b are each separated from the pump chamber 3 by a partition wall 1a and communicated with the pump chamber 3 by a plurality of vent holes 6 penetrating the partition wall 1a.
[0016]
The vent hole 6 that communicates the intake chamber 3a and the pump chamber 3 is covered on the pump chamber 3 side by a rubber check valve 7a that penetrates the partition wall 1a. Further, the vent holes 6 that communicate the exhaust chamber 3b and the pump chamber 3 are covered on the exhaust chamber 3b side by a rubber check valve 7b that penetrates the partition wall 1a.
[0017]
In the cam chamber 4, a cylindrical piston (tubular body) 8 attached concentrically with the diaphragm 20 is disposed at the center of the diaphragm 20, and the cylindrical piston 8 has a cylinder held by the pump case 2. A cam (rotating shaft) 10 is loosely fitted, and the cylindrical cam 10 is connected to an output rotating shaft 9 a of the drive motor 9.
[0018]
The diaphragm 20 is a thin film made of a material having flexibility such as rubber, and a through hole 21 is formed at the center, and an annular bulging protrusion 22 protruding along the axial direction at the peripheral part is concentric with the through hole 21. Is formed.
[0019]
As shown in FIG. 2, the cylindrical piston 8 has a cylindrical shape with both ends open, and two guide protrusions 11a and 11b are integrally provided on the inner peripheral surface 8a.
[0020]
The guide protrusions 11a and 11b are provided at positions corresponding to the same phase of two cam groove portions 13a and 13b that form a cam groove 12 described later.
[0021]
As shown in FIG. 2, the cylindrical cam 10 has a columnar shape having an outer diameter substantially equal to the inner diameter of the cylindrical piston 8, and a wavy cam groove 12 extending in the circumferential direction is provided on the outer peripheral surface 10 a in an annular shape. Yes.
[0022]
FIG. 3 is a circumferential development of the outer peripheral surface 10a of the cylindrical cam 10, and the cam groove 12 is formed by connecting two cam groove portions 13a and 13b having the same wave shape.
[0023]
The cam grooves 13a and 13b have a U-shaped cross-section in which the guide protrusions 11a and 11b are fitted (see FIG. 1), and each wave having a sine curve of one cycle when the development is viewed from the front. It is in shape.
[0024]
Therefore, for example, when rotating with reference to the point T ₁ located in the axial center 10 a of the cylindrical cam 10, the point bulging most upward in the axial direction of the cylindrical cam 10 (hereinafter referred to as “upper”) When a single starting point a) is formed and rotated by 90 °, a point T ₂ located at the axial center 10a of the cylindrical cam 10 is obtained.
[0025]
One point bulging most downward in the axial direction of the cylindrical cam (hereinafter referred to as the lower starting point b) is formed before rotating 180 °, and when it is rotated 180 °, the cylindrical cam 10 is positioned at the central portion 10a in the axial direction. the point T ₃ to.
[0026]
Further, one upper start point a is formed before the rotation by 270 °, and when the rotation is made 270 °, the point T ₄ is located at the central portion 10a in the axial direction of the cylindrical cam 10.
[0027]
One lower start point b is formed before the rotation by 360 °, and when the rotation is performed by 360 °, the point T ₅ overlaps the reference point T ₁ .
[0028]
Incidentally, while the points T ₁ ~ point T ₃ is the cam groove 13a, between the points T ₃ ~ point T ₅ is cam groove 13b.
[0029]
The cam grooves 13a and 13b have the same length A between the upper start point a and the axial center portion 10a of the cylindrical cam 10 and the distance B between the lower start point b and the axial center portion 10a of the cylindrical cam 10. It has been.
[0030]
The diaphragm 20 is positioned concentrically with the cylindrical piston 8 with the annular bulging protrusion 22 protruding toward the pump chamber 3, and the through hole 21 and the cylindrical piston 8 have a mounting member 24 having a flange 24 a. Has been inserted. The diaphragm 20 is attached to the cylindrical piston 8 by sandwiching the peripheral edge of the through hole 21 between the flange 24 a of the attachment member 24 and one end of the cylindrical piston 8.
[0031]
A peripheral edge 20 a of the diaphragm 20, which is an outer peripheral edge of the annular bulging protrusion 22, is sandwiched and fixed between the pump chamber 3 and the cam chamber 4.
[0032]
The cylindrical piston 8 has a cylindrical cam 10 which is rotatable and coaxially fitted, and guide projections 11a and 11b are provided at positions corresponding to the same phase of the two cam groove portions 13a and 13b, for example, points T ₁ and T ₃ . Each is fitted (see FIG. 3).
[0033]
Further, the cylindrical cam 10 is held in the pump case 2 so as to be rotatable and immovable in the axial direction, and the rotating shaft 10b of the cylindrical cam 10 is connected to the output rotating shaft 9a of the drive motor 9 disposed coaxially. .
[0034]
Next, the operation of the air pump 1 will be described.
[0035]
In order to drive the air pump 1, first, the drive motor 9 is driven to rotate the output rotating shaft 9a. When the output rotation shaft 9a rotates, the cylindrical cam 10 connected to the output rotation shaft 9a is driven to rotate about the axis.
[0036]
Then, the circumferential position of the cam groove 12 is changed by the rotation of the cylindrical cam 10. At this time, the guide protrusions 11 a and 11 b fitted in the cam groove 12 do not change in the circumferential position, but change in the axial position along the sine curve shape of the cam groove 12.
[0037]
Since the two guide protrusions 11a and 11b are fitted in positions corresponding to the same phase of the two cam groove portions 13a and 13b forming the cam groove 12, they can be smoothly slid without hindering each other's movement. Can move.
[0038]
When the guide protrusions 11a and 11b move relatively from the points T ₁ and T ₃ toward the upper start point a, the cylindrical piston 8 performs a linear motion toward the pump chamber 3 side.
[0039]
At this time, as shown in FIG. 4A, the diaphragm 20 is deformed to the pump chamber 3 side, the volume of the pump chamber 3 is reduced, and the atmospheric pressure in the pump chamber 3 is increased. Then, the gas pushes open the check valve 7b provided on the outer wall side of the intake / exhaust chamber 3c through the vent holes 6 ..., flows into the exhaust chamber 3b, and is then discharged into the outside air from the exhaust opening 5b.
[0040]
The annular bulging protrusion 22 of the diaphragm 20 is extended toward the pump chamber 3 along with the cylindrical piston 8 toward the pump chamber 3, and the through-hole 21 of the diaphragm 20 and the peripheral portion 20 a of the diaphragm 20. The tensile force generated during the period is relaxed.
[0041]
When the guide protrusions 11a and 11b are positioned at the upper start point a, the diaphragm 20 moves most to the pump chamber 3 side, and this moving distance is the distance A between the upper start point a and the axial center portion 10a of the cylindrical cam 10. This is the deformation stroke A on the pump chamber 3 side.
[0042]
Then, the guide projection 11a, the 11b moves relatively respectively toward the point T _2, T _4, cylindrical piston 8 performs a linear motion toward the cam chamber 4, guide projections to the point T _2, T ₄ When 11a and 11b are positioned, the deformation of the diaphragm 20 returns to a normal shape.
[0043]
Further, when the guide protrusions 11a and 11b move relatively toward the lower starting point b, the cylindrical piston 8 performs a linear motion toward the cam chamber 4 side.
[0044]
At this time, as shown in FIG. 4A, the diaphragm 20 is deformed to the cam chamber 4 side, the volume of the pump chamber 3 is expanded, and the atmospheric pressure in the pump chamber 3 is lowered. Then, after the gas is sucked from the intake port 5a and flows into the intake chamber 3a, the check valve 7a provided on the inner wall side of the intake / exhaust chamber 3c is pushed through the vent holes 6 ... to open the inside of the intake / exhaust chamber 3c. Sucked into.
[0045]
The annular bulging protrusion 22 of the diaphragm 20 is extended toward the cam chamber 4 along with the cylindrical piston 8 directed toward the cam chamber 4, and the through-hole 21 of the diaphragm 20 and the peripheral portion 20 a of the diaphragm 20. The tensile force generated during the period is relaxed.
[0046]
When the guide protrusions 11a and 11b are positioned at the lower starting point b, the diaphragm 20 moves most toward the cam chamber 4 side, and this moving distance is the distance B between the lower starting point b and the axial center portion 10a of the cylindrical cam 10. This is the deformation stroke B on the cam chamber 4 side.
[0047]
When the guide protrusions 11a and 11b move relative to the points T ₃ and T ₅ , respectively, the cylindrical piston 8 performs a linear motion toward the pump chamber 3, and the guide protrusions 11a and 11b are respectively connected to the points T ₃ and T ₅ . when located in T _5, the deformation of the diaphragm 20 will return normal shape.
[0048]
Thus, when the cylindrical cam 10 rotates, the cam groove 12 and the guide protrusions 11a and 11b can slide relative to each other and move relatively in the axial direction.
[0049]
Since the cam groove 12 has a sinusoidal wave shape, the cylindrical piston 8 performs a reciprocating linear motion that is deformed by the deformation stroke A on the pump chamber 3 side and moves by the deformation stroke B on the cam chamber 4 side. Thus, the diaphragm 20 can be deformed along the axial direction.
[0050]
Therefore, it is possible to suppress noise, vibration, and the like caused by the intake / exhaust of gas, and to intake / exhaust gas from the pump chamber 3 while preventing early deterioration of the diaphragm member 20.
[0051]
And it becomes possible to arrange | position the diaphragm 20, the cylindrical piston 8, the cylindrical cam 10, and the drive motor 9 on the same axis | shaft, and can attain size reduction.
[0052]
Further, by supporting the diaphragm 20 by the two guide protrusions 11a and 11b, it is possible to prevent the diaphragm 20 from being inclined with respect to the axial direction.
[0053]
As described above, the embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to the above-described embodiment, and even if there is a design change or the like without departing from the gist of the present invention. It is included in this invention.
[0054]
For example, as shown in the developed view of the outer peripheral surface 10a of the cylindrical cam 10 shown in FIG. 5, the deformation stroke A when the diaphragm 20 is deformed toward the pump chamber 3 with reference to the neutral point T ... where the diaphragm 8 is not deformed. The shape of the cam groove 12 may be different from 'and the deformation stroke B' when deforming toward the cam chamber 4 side.
[0055]
Here, the deformation stroke A ′ when the diaphragm 20 is deformed toward the pump chamber 3 side which is the projecting direction of the annular bulging protrusion 22 is made larger than the deformation stroke B ′ when the diaphragm 20 is deformed to the opposite side. Yes.
[0056]
Thereby, the volume change in the pump chamber 3 between the case where the diaphragm 20 is directed to the pump chamber 3 side and the case where the diaphragm 20 is directed to the cam chamber 4 side can be made uniform. In addition, the intake air amount and the exhaust air amount become equal, and the pump efficiency can be improved.
[0057]
In addition, a wavy annular groove serving as the cam groove 12 is provided on the inner peripheral surface 8a of the cylindrical piston 8, and the guide is fitted to the annular groove serving as the guide protrusions 11a and 11b on the outer peripheral surface 10a of the cylindrical cam 10. The protrusions may be provided integrally.
[0058]
Furthermore, although not shown here, the cam groove may be formed by connecting three or more cam groove portions having the same wave shape. In that case, it is preferable that the number of the guide protrusions is the same as the number of the cam groove portions, and the guide protrusions are respectively fitted at positions corresponding to the same phase of the cam groove portions to support the diaphragm 20 and prevent the diaphragm from being inclined.
[0059]
【The invention's effect】
According to the present invention, it is possible to provide an air pump that is unlikely to deteriorate and that can suppress vibrations, noises, and the like that occur during gas intake and exhaust, and can be downsized.
[Brief description of the drawings]
FIG. 1 is a partially broken sectional view of an air pump according to the present invention.
FIG. 2 is an explanatory view of a cylindrical piston member and a cylindrical cam of the present invention.
FIG. 3 is a development view of the outer peripheral surface of the cylindrical cam of the present invention.
FIG. 4A is an explanatory diagram when air is taken in by the air pump of the present invention. (B) It is explanatory drawing at the time of exhausting with the air pump of this invention.
FIG. 5 is a development view of another example of the outer peripheral surface of the cylindrical cam of the present invention.
FIG. 6 is an explanatory diagram of a conventional air pump.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Air pump 2 Pump case 3 Pump chamber 3a Intake port 3b Exhaust port 4 Cam chambers 7a and 7b Check valve 8 Cylindrical piston (cylinder)
8a Inner peripheral surface 9 Drive motor 10 Cylindrical cam (rotary shaft)
10a Outer peripheral surface 11a, 11b Guide protrusion 12 Annular cam 20 Diaphragm

Claims (2)

A pump case and a diaphragm that divides the inside of the pump case into a pump chamber and a cam chamber, wherein the pump case is formed with an intake port and an exhaust port that are open to the pump chamber; A check valve for allowing air flow to the chamber, and an air pump having a check valve for allowing air flow to the outside of the pump chamber at the exhaust port,
A cylinder disposed in the cam chamber and attached to the center of the diaphragm concentrically with the diaphragm, and freely fitted in the cylinder so as to be rotatable and relatively movable in the axial direction, and the pump A rotating shaft held in the case so as to be rotatable and immovable in the axial direction; and a drive motor for rotating the rotating shaft around the axis.
An annular bulging protrusion that protrudes into the pump chamber or cam chamber is formed concentrically on the peripheral edge of the diaphragm,
Either one of the inner peripheral surface of the cylindrical body and the outer peripheral surface of the rotary shaft is provided with an annular cam groove extending in the circumferential direction, and the other is integrally provided with a guide projection that fits into the cam groove. Provided in
The cam groove has a deformation stroke when the diaphragm is deformed toward the projecting direction of the annular bulging protrusion, and the cam groove is deformed toward a direction opposite to the projecting direction of the annular bulging protrusion. An air pump characterized by having a shape larger than the deformation stroke .   2. The air pump according to claim 1, wherein the cam groove is annularly formed by connecting a plurality of wavy cam groove portions in the circumferential direction that reciprocate the cylindrical body and the rotating shaft at least once in the axial direction. An air pump characterized in that a plurality of the guide protrusions are provided and are respectively fitted at positions corresponding to the same phase of the plurality of wavy cam groove portions.

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