JP5531038B2

JP5531038B2 - Diaphragm

Info

Publication number: JP5531038B2
Application number: JP2012032002A
Authority: JP
Inventors: 学藤田
Original assignee: 多田プラスチック工業株式会社
Priority date: 2012-02-16
Filing date: 2012-02-16
Publication date: 2014-06-25
Anticipated expiration: 2032-02-16
Also published as: JP2013167227A

Description

本発明は、ダイヤフラムに関する。 The present invention relates to a diaphragm.

従来、流体を圧送するための流体用ダイヤフラムポンプに用いられるダイヤフラムは、縮小（圧縮）・拡大されるポンプ室の一部を形成する円筒壁部と、ポンプ室を縮小（圧縮）・拡大するための円柱状の駆動軸部と、円筒壁部と駆動軸部と連結する横断面Ｌ字状の連結壁部と、を一体成型したものが知られている（例えば、特許文献１参照）。
即ち、図７と図８に示すように、従来のダイヤフラム９は、円筒壁部91と、自由状態で円筒壁部91に同軸心状に配設される円柱状の駆動軸部93と、円筒壁部91と駆動軸部93と連結する横断面Ｌ字状の連結壁部92とを、一体成型していた。
従来の連結壁部92は、駆動軸部93の外周面からラジアル外方へ突出するにつれて次第に軸心一方向Ｎ１´に弯曲して円筒壁部91と連結する横断面Ｌ字状に形成され、肉厚寸法ｔ´は、均一であった。 Conventionally, a diaphragm used for a diaphragm pump for fluid for pumping fluid is a cylindrical wall part that forms a part of a pump chamber to be reduced (compressed) or enlarged, and a pump chamber is reduced (compressed) or enlarged. A cylindrical drive shaft part and a cylindrical wall part and a connecting wall part having an L-shaped cross section connected to the drive shaft part are integrally molded (for example, see Patent Document 1).
That is, as shown in FIGS. 7 and 8, the conventional diaphragm 9 includes a cylindrical wall portion 91, a columnar drive shaft portion 93 disposed coaxially with the cylindrical wall portion 91 in a free state, and a cylindrical shape. The wall 91 and the connecting wall 92 having an L-shaped cross section connected to the drive shaft 93 are integrally formed.
The conventional connecting wall portion 92 is formed in a L-shaped cross section that gradually bends in one axial center direction N1 ′ and connects to the cylindrical wall portion 91 as it protrudes radially outward from the outer peripheral surface of the drive shaft portion 93. The wall thickness dimension t ′ was uniform.

特開２００９−４１５３８号公報JP 2009-41538 A

そのため、従来の連結壁部92と駆動軸部93の連結部位Ｅ´は、急激に厚みが変化する段付き形状となり、応力集中が発生する虞の高い形状であった。
特に、図８に示すように、駆動軸部93が往復運動すると、連結部位Ｅ´は、小さい鋭角に折られると共に、強い曲げ応力（引張力や圧縮力）を受けていた。従って、応力集中が発生すると共に、繰り返しによる疲労が蓄積されて、亀裂や破れ、切断等の損傷が発生し、耐久性に問題があることが判明した。 Therefore, the connecting portion E ′ between the conventional connecting wall portion 92 and the drive shaft portion 93 has a stepped shape whose thickness changes abruptly, and has a shape that is highly likely to cause stress concentration.
In particular, as shown in FIG. 8, when the drive shaft portion 93 reciprocates, the connection portion E ′ is bent at a small acute angle and receives a strong bending stress (tensile force or compressive force). Accordingly, it was found that stress concentration occurs and fatigue due to repetition accumulates, resulting in damage such as cracks, tears, and cutting, and there is a problem in durability.

そこで、本発明は、耐久性に優れ、長期間使用可能なダイヤフラムの提供を目的とする。 Therefore, an object of the present invention is to provide a diaphragm that is excellent in durability and can be used for a long period of time.

上記目的を達成するために、本発明のダイヤフラムは、縮小と拡大が繰り返されるポンプ室の一部を形成する円筒壁部と、自由状態で該円筒壁部に同軸心状に配設されると共に上記ポンプ室を縮小・拡大させるための駆動軸部と、上記円筒壁部と上記駆動軸部と連結する連結壁部とを、一体成型したダイヤフラムに於て、上記連結壁部は、自由状態で、上記駆動軸部の一端面の周縁部から軸心一方向に突出しつつラジアル外方向へ弯曲する第１弯曲壁部と、軸心直交状の平面状壁部と、ラジアル外方に延伸しつつ上記軸心一方向に弯曲して上記円筒壁部に連続する第２弯曲壁部とを、一体連続状に有する横断面Ｓ字状に形成され、上記連結壁部の上記第１弯曲壁部が、上記駆動軸部の上記一端面に接近するにつれて、肉厚寸法がしだいに増加するように形成されているものである。
また、上記円筒壁部の内径寸法をＤ₁₀、上記駆動軸部の上記一端面の外径寸法をｄとすると、０．４５・Ｄ₁₀≦ｄ≦０．６０・Ｄ₁₀なる数式が成立するように、上記駆動軸部の上記外径寸法を小さく設定したものである。 In order to achieve the above object, a diaphragm according to the present invention is provided with a cylindrical wall part forming a part of a pump chamber that is repeatedly reduced and enlarged, and coaxially disposed on the cylindrical wall part in a free state. A diaphragm in which a driving shaft for reducing and enlarging the pump chamber and a connecting wall connected to the cylindrical wall and the driving shaft are integrally formed. In the diaphragm, the connecting wall is in a free state. A first curved wall portion that is curved in a radial outward direction while projecting in one axial direction from a peripheral edge portion of one end surface of the drive shaft portion, a planar wall portion that is orthogonal to the axial center, and a radial outward direction. the shaft and the heart one direction and curved second curved wall portion continuous with the cylindrical wall portion, is formed on the cross section S-shape having integrally continuous shape, the upper Symbol connecting wall portion of the first curved wall section However, as it approaches the one end surface of the drive shaft portion, the wall thickness gradually increases. Are those formed so that.
Further, when the inner diameter dimension of the cylindrical wall portion is D ₁₀ and the outer diameter dimension of the one end surface of the drive shaft portion is d, the following equation is established: 0.45 · D ₁₀ ≦ d ≦ 0.60 · D ₁₀ As described above, the outer diameter of the drive shaft portion is set to be small.

本発明によれば、ポンプ室を拡大・縮小する際に、駆動軸部と連結壁部の連結部位に、応力集中が発生するのを緩和して、亀裂等の損傷を防止できる。耐久性が向上し、長期間にわたって使用できる（寿命が延びる）。 According to the present invention, when the pump chamber is enlarged / reduced, it is possible to alleviate the occurrence of stress concentration at the connection portion between the drive shaft portion and the connection wall portion, and to prevent damage such as cracks. Durability is improved, and it can be used for a long period of time (life is extended).

本発明の実施の一形態を示す縦断面図である。It is a longitudinal cross-sectional view which shows one Embodiment of this invention. 要部拡大断面図である。It is a principal part expanded sectional view. 要部拡大断面図である。It is a principal part expanded sectional view. 作用説明図である。It is an operation explanatory view. 使用状態の一例を具体的に示したダイヤフラムポンプの要部断面図である。It is principal part sectional drawing of the diaphragm pump which showed an example of the use condition concretely. ダイヤフラム集合体とした場合を具体的に示した斜視図である。It is the perspective view which showed specifically the case where it was set as the diaphragm assembly. 従来例の縦断面図である。It is a longitudinal cross-sectional view of a prior art example. 従来例の使用状態を説明する要部断面図である。It is principal part sectional drawing explaining the use condition of a prior art example.

以下、図示の実施形態に基づき本発明を詳説する。
本発明に係るダイヤフラム３は、図１に示す実施の一形態に於て、縮小と拡大が繰り返されるポンプ室１の一部を形成する円筒壁部10と、自由状態で円筒壁部10に同軸心状に配設されると共にポンプ室１を縮小・拡大させるための円柱状の駆動軸部30と、円筒壁部10と駆動軸部30を連結する連結壁部20と、を一体成型したゴム製のダイヤフラムである。なお、図１では、円筒壁部10と連結壁部20と駆動軸部30と他部との境界（線）を一軸心Ｌと直交する二点鎖線Ｓ１，Ｓ２，Ｓ３，Ｓ４にて示している。一軸心Ｌは、自由状態のダイヤフラム３の軸心であり、また、円筒壁部10の軸心とも言える。
図６に例示するように、３個のダイヤフラム３，３，３を横膜部11と一体成型する等、複数個のダイヤフラム３を一体構造とする（ダイヤフラム集合体13とする）のが望ましい。但し、ダイヤフラム３を単数個ずつ成型して、これを１個のダイヤフラムポンプに複数個組立てて使用するも自由である。
図５に於て、本発明に係るダイヤフラム３を組込んだダイヤフラムポンプ２の一例を示し、図６にて述べたダイヤフラム集合体13を適用している。駆動軸部30から斜板14の孔部に挿入して組立てられる連結軸部15が延設されている。アクチュエータ17の出力軸18が回転すると、斜板14が偏心運動を起こし、ダイヤフラム３は、図５の左側に示した膨張状態と、図５の右側に示した圧縮（縮小）状態とに交互に切換わり、かつ、弁体19と弁座部24の弁機能によって、矢印25の方向から流体を吸い込んで、圧力流体が矢印26方向に吐出する。 Hereinafter, the present invention will be described in detail based on illustrated embodiments.
In the embodiment shown in FIG. 1, the diaphragm 3 according to the present invention is coaxial with the cylindrical wall portion 10 that forms part of the pump chamber 1 that is repeatedly reduced and enlarged, and in the free state. A rubber which is integrally formed with a cylindrical drive shaft portion 30 for reducing and expanding the pump chamber 1 and a connecting wall portion 20 for connecting the cylindrical wall portion 10 and the drive shaft portion 30. It is a made diaphragm. In FIG. 1, boundaries (lines) between the cylindrical wall portion 10, the connecting wall portion 20, the drive shaft portion 30, and other portions are indicated by two-dot chain lines S 1, S 2, S 3, and S 4 that are orthogonal to the uniaxial center L. ing. The single axis L is the axis of the diaphragm 3 in a free state, and can also be said to be the axis of the cylindrical wall portion 10.
As illustrated in FIG. 6, it is desirable that a plurality of diaphragms 3 have an integral structure (ie, a diaphragm assembly 13), for example, three diaphragms 3, 3, 3 are integrally formed with the transverse membrane portion 11. However, it is also free to mold a single diaphragm 3 one by one and assemble a plurality of them into one diaphragm pump.
In FIG. 5, an example of the diaphragm pump 2 incorporating the diaphragm 3 according to the present invention is shown, and the diaphragm assembly 13 described in FIG. 6 is applied. A connecting shaft portion 15 that is assembled by being inserted into the hole portion of the swash plate 14 from the drive shaft portion 30 is extended. When the output shaft 18 of the actuator 17 rotates, the swash plate 14 undergoes an eccentric motion, and the diaphragm 3 alternates between an expanded state shown on the left side of FIG. 5 and a compressed (reduced) state shown on the right side of FIG. The fluid is sucked from the direction of the arrow 25 by the valve function of the valve body 19 and the valve seat portion 24, and the pressure fluid is discharged in the direction of the arrow 26.

図１及び図２に於て、連結壁部20は、未装着の自由状態で、駆動軸部30の一端面32の周縁部（外周縁部）32ａから一軸心Ｌの軸心一方向Ｎ１に突出するにつれて次第にラジアル外方に弯曲する第１弯曲壁部21と、第１弯曲壁部21の先端21ａから（駆動軸部30）ラジアル外方へ向かって一軸心Ｌに直交する平面状（軸心直交状と呼ぶ場合もある）に形成される円環平面状壁部22と、円環平面状壁部22の外径端縁部22ａからラジアル外方へ向かうにつれて次第に軸心一方向Ｎ１に弯曲して円筒壁部10に連結する第２弯曲壁部23と、を有する横断面略Ｓ字状に形成されている。
なお、図１及び図２では、第１弯曲壁部21と円環平面状壁部22の境界を一軸心Ｌと平行な二点鎖線Ｊ１にて示している。また、円環平面状壁部22と第２弯曲壁部23の境界を一軸心Ｌと平行な二点鎖線Ｊ２にて示している。 1 and 2, the connecting wall portion 20 is in a free state in which it is not mounted, and the axial center direction N1 of the uniaxial center L from the peripheral edge portion (outer peripheral edge portion) 32a of the one end face 32 of the drive shaft portion 30. A first curved wall portion 21 that gradually bends radially outward as it protrudes toward the center, and a planar shape perpendicular to the uniaxial center L from the tip 21a of the first curved wall portion 21 (drive shaft portion 30) radially outward. An annular planar wall portion 22 formed in a shape (which may be referred to as an axially orthogonal shape), and gradually toward the axial center as it goes radially outward from the outer diameter end edge portion 22a of the annular planar wall portion 22. It is formed in a substantially S-shaped cross section having a second bent wall portion 23 that is bent at N1 and connected to the cylindrical wall portion 10.
1 and 2, the boundary between the first bent wall portion 21 and the annular planar wall portion 22 is indicated by a two-dot chain line J1 parallel to the uniaxial center L. The boundary between the annular planar wall portion 22 and the second curved wall portion 23 is indicated by a two-dot chain line J2 parallel to the uniaxial center L.

図２及び図３に於て、第１弯曲壁部21は、未装着の自由状態で、基端部21ｂに、横断面形状で駆動軸部30の外周面31と一軸心Ｌに平行な直線状に連続する基端外周面51と、駆動軸部30の軸心直交平面状の一端面32と連続する弯曲凹状（凹Ｒ状）の基端内周面52と、を有している。
また、第１弯曲壁部21は、中間部21ｃに、弯曲凹状（凹Ｒ状）の中間外周面53と、弯曲凸状（凸Ｒ状）の中間内周面54と、を有している。
なお、図２では、駆動軸部30と連結壁部20の境界を二点鎖線Ｓ３にて示している。また、第１弯曲壁部21の基端部21ｂと中間部21ｃの境界を一軸心Ｌと直交する二点鎖線Ｋ１で示し、中間部21ｃと先端部21ｄの境界を一軸心Ｌと平行な二点鎖線Ｋ２にて示している。 2 and 3, the first curved wall portion 21 is parallel to the outer peripheral surface 31 of the drive shaft portion 30 and the uniaxial center L in a cross-sectional shape at the base end portion 21b in a free state in which it is not mounted. It has a base end outer peripheral surface 51 that is continuous in a straight line, and a base end inner peripheral surface 52 that is a curved concave shape (concave R shape) that is continuous with an end surface 32 that is orthogonal to the axial center of the drive shaft portion 30. .
In addition, the first curved wall portion 21 has a curved concave (concave R-shaped) intermediate outer peripheral surface 53 and a curved convex (convex R-shaped) intermediate inner peripheral surface 54 at the intermediate portion 21c. .
In FIG. 2, the boundary between the drive shaft portion 30 and the connecting wall portion 20 is indicated by a two-dot chain line S3. Further, the boundary between the base end portion 21b and the intermediate portion 21c of the first bent wall portion 21 is indicated by a two-dot chain line K1 orthogonal to the uniaxial center L, and the boundary between the intermediate portion 21c and the distal end portion 21d is parallel to the uniaxial center L. This is indicated by a two-dot chain line K2.

図３に於て、基端内周面52は、基端半径寸法Ｒａで形成されている。
中間外周面53は、第１半径寸法Ｒ１で形成されている。中間内周面54は第１半径寸法Ｒ１より大きな第２半径寸法Ｒ２で形成されている。そして、中間内周面54（第２半径寸法Ｒ２）の中心点を、中間外周面53（第１半径寸法Ｒ１）の中心点よりも、一軸心Ｌ寄り（駆動軸部30）に配設している。 In FIG. 3, the base end inner peripheral surface 52 is formed with a base end radial dimension Ra.
The intermediate outer peripheral surface 53 is formed with a first radius dimension R1. The intermediate inner peripheral surface 54 is formed with a second radial dimension R2 larger than the first radial dimension R1. The central point of the intermediate inner peripheral surface 54 (second radial dimension R2) is disposed closer to the uniaxial center L (drive shaft portion 30) than the central point of the intermediate outer peripheral surface 53 (first radial dimension R1). doing.

つまり、基端部21ｂの肉厚寸法ｔ（ｔ１）及び中間部21ｃの肉厚寸法ｔ（ｔ２）は、駆動軸部30の一端面32から円環平面状壁部22側へ向かうにつれて次第に肉厚寸法ｔが小さくなるように形成されている。基端部21ｂ及び中間部21ｃは段差無く滑らかに連続状に形成されている。
言い換えると、基端部21ｂ及び中間部21ｃは、円環平面状壁部22側から駆動軸部30に向かうにつれて次第に肉厚寸法ｔが大きくなるように形成されている。 That is, the wall thickness t (t1) of the base end portion 21b and the wall thickness t (t2) of the intermediate portion 21c are gradually increased from the one end surface 32 of the drive shaft portion 30 toward the annular planar wall portion 22 side. The thickness dimension t is formed to be small. The base end portion 21b and the intermediate portion 21c are formed smoothly and continuously without a step.
In other words, the base end portion 21b and the intermediate portion 21c are formed such that the wall thickness t gradually increases from the annular planar wall portion 22 side toward the drive shaft portion 30.

なお、第２半径寸法Ｒ２は、第１半径寸法Ｒ１の１.５〜３倍、好ましくは、２〜２．７倍に設定するのが好ましい、上述の上限値を越えると、急激に肉厚寸法ｔが変化して、応力集中が発生する虞がある。下限値未満であると肉厚寸法ｔが均一状となって基端部21ｂ寄りで応力集中が発生する虞がある。
また、基端半径寸法Ｒａと第１半径寸法Ｒ１は、同等の大きさに設定することで、段差無く滑らかで急激な肉厚変化がなく応力集中の発生を緩和可能な形状としている。 The second radius dimension R2 is preferably set to 1.5 to 3 times, preferably 2 to 2.7 times the first radius dimension R1. There is a possibility that stress concentration occurs due to a change in the dimension t. If it is less than the lower limit value, the thickness dimension t is uniform, and stress concentration may occur near the base end 21b.
In addition, by setting the proximal radius dimension Ra and the first radius dimension R1 to be equal to each other, the shape is smooth without a step and without a sudden change in thickness, and can reduce the occurrence of stress concentration.

また、第１弯曲壁部21の先端部21ｄは、その肉厚寸法ｔ（ｔ３）が、平面状壁部22の肉厚寸法ｔ（ｔ４）と同等で、平面状壁部22に滑らか（無段差）に接続している。
また、平面状壁部22の肉厚寸法ｔ（ｔ４）と第２弯曲壁部23の肉厚寸法ｔ（ｔ５）は同等に形成され、第２弯曲壁部23に滑らかに連結している。 Further, the tip end portion 21d of the first bent wall portion 21 has a thickness dimension t (t3) equal to the thickness dimension t (t4) of the planar wall portion 22, and is smooth (nothing) on the planar wall portion 22. Connected to the step).
Moreover, the thickness dimension t (t4) of the planar wall portion 22 and the thickness dimension t (t5) of the second curved wall portion 23 are formed to be equal to each other and are smoothly connected to the second curved wall portion 23.

また、図１に於て、第２弯曲壁部23の肉厚寸法ｔ（ｔ５）と円筒壁部10の（横膜部11よりも下方側の）肉厚寸法ｔ（ｔ６）は同等に形成され、円筒壁部10に滑らかに連結している。
また、第２弯曲壁部23の内周面は第３半径寸法Ｒ３で形成され、外周面は第３半径寸法Ｒ３と中心点が同じで第３半径寸法Ｒ３より僅か（肉厚寸法ｔ分だけ）大きい第４半径寸法で形成されている。即ち、第２弯曲壁部23は肉厚寸法ｔが均一に形成されている。 In FIG. 1, the thickness dimension t (t5) of the second curved wall portion 23 and the thickness dimension t (t6) of the cylindrical wall portion 10 (below the lateral membrane portion 11) are formed to be equal. And is smoothly connected to the cylindrical wall portion 10.
Further, the inner peripheral surface of the second curved wall portion 23 is formed with the third radius dimension R3, and the outer peripheral surface has the same center point as the third radius dimension R3 and is slightly smaller than the third radius dimension R3 (by the thickness t). ) It is formed with a large fourth radius dimension. That is, the second bent wall portion 23 is formed with a uniform thickness dimension t.

また、円筒壁部10の内径寸法をＤ₁₀、駆動軸部30の一端面32の外径寸法をｄとすると、０．４５・Ｄ₁₀≦ｄ≦０．６０・Ｄ₁₀なる数式が成立するように、駆動軸部30の外径寸法を小さく設定した構成である。下限値未満であると、駆動軸部30が図５に示したように斜板14から受ける外力を、円滑に第１弯曲壁部21や第２弯曲壁部23へ伝達できず、局部的に無理な（過大な）応力を発生して、ダイヤフラム３の寿命が急に短くなる。逆に上限値を越えると、第１弯曲壁部21や第２弯曲壁部23が短くなって弾性変形が困難になり、応力集中を緩和できなくなる（応力集中が発生する）虞がある。
なお、図１と図５に示すように、横膜部11よりも上方側の円筒壁部10の肉厚寸法が小さく設定されて、さらに、上方へ延伸して、円筒弁部12が連設される。 When the inner diameter dimension of the cylindrical wall portion 10 is D ₁₀ and the outer diameter dimension of the one end surface 32 of the drive shaft portion 30 is d, the following equation is established: 0.45 · D ₁₀ ≦ d ≦ 0.60 · D ₁₀ Thus, the outer diameter dimension of the drive shaft 30 is set to be small. If it is less than the lower limit value, the external force received by the drive shaft 30 from the swash plate 14 as shown in FIG. 5 cannot be smoothly transmitted to the first and second curved wall portions 21 and 23, and locally. An unreasonable (excessive) stress is generated, and the life of the diaphragm 3 is suddenly shortened. On the contrary, if the upper limit is exceeded, the first bent wall portion 21 and the second bent wall portion 23 are shortened, making it difficult to elastically deform, and stress concentration cannot be relaxed (stress concentration occurs).
As shown in FIGS. 1 and 5, the wall thickness of the cylindrical wall portion 10 on the upper side of the transverse membrane portion 11 is set to be small, and the cylindrical valve portion 12 is continuously provided by extending upward. Is done.

なお、図５に示す流体用ダイヤフラムポンプ２は、ケーシング６や斜板14、伝達軸８、傘状弁体19等を備え、伝達軸８が、出力軸18の軸心廻りに周回して、伝達軸８に取り付けられる斜板14が、ダイヤフラム駆動軸部30を往復運動させて、複数個のダイヤフラムが順次ポンプ室１を膨縮（拡大・圧縮）させることで、ポンプ動作を行なう複数気筒型である。 The fluid diaphragm pump 2 shown in FIG. 5 includes a casing 6, a swash plate 14, a transmission shaft 8, an umbrella-shaped valve body 19, etc., and the transmission shaft 8 circulates around the axis of the output shaft 18. A swash plate 14 attached to the transmission shaft 8 reciprocates the diaphragm drive shaft portion 30, and a plurality of diaphragms sequentially expands and contracts (expands / compresses) the pump chamber 1, thereby performing a pump operation. It is.

なお、本発明は、設計変更可能であって、単気筒型の流体用ポンプに使用しても良い。 The present invention can be modified in design and may be used for a single cylinder type fluid pump.

次に、本発明のダイヤフラムの作用について説明する。
図４に示すように、実線で示すダイヤフラム３は、装着基準状態を示し、図１に示した未装着の自由状態に比べて、駆動軸部30が軸心一方向Ｎ１に移動した状態で斜板14によって保持されている。そして、アクチュエータ17が駆動すると、斜板14が揺動し、二点鎖線で示すように駆動軸部30の軸心Ｌａが一軸心Ｌに対して傾斜状に配設され軸心一方向Ｎ１側へ押されポンプ室１を圧縮状態にする圧縮姿勢と、二点鎖線で示すように駆動軸部30の軸心Ｌａが一軸心Ｌに対して傾斜状に配設され軸心他方向Ｎ２側へ引かれてポンプ室１を拡大（膨張）する拡大姿勢と、に繰り返し変化して、ポンプ室１を膨縮するポンプ作動を行なう（図５参照）。 Next, the operation of the diaphragm of the present invention will be described.
As shown in FIG. 4, the diaphragm 3 indicated by a solid line shows a mounting reference state, and is inclined in a state in which the drive shaft portion 30 has moved in one axial direction N <b> 1 compared to the unmounted free state shown in FIG. 1. It is held by a plate 14. When the actuator 17 is driven, the swash plate 14 swings, and the shaft center La of the drive shaft portion 30 is inclined with respect to the one axis L as indicated by a two-dot chain line, and the shaft center is in one direction N1. And the shaft center La of the drive shaft 30 is inclined with respect to the uniaxial center L as shown by the two-dot chain line, and is compressed in the compressed state to push the pump chamber 1 into the compressed state. The pump operation of expanding and contracting the pump chamber 1 is performed by repeatedly changing to an expanded posture in which the pump chamber 1 is expanded (expanded) by being pulled to the side (see FIG. 5).

図４と図５に示すように、ポンプ作動中は、駆動軸部30と連結壁部20の連結部位Ｅは、急に折曲げられることがなく、応力集中が発生するのが緩和されている。即ち、従来例を示した図８と、本発明を示した図５及び図４を比較すれば判るように、連結壁部20は極端に折曲がることなく、全体Ｓ字状に弾性的に弯曲変形し、応力集中箇所も生ずることなく、疲労に伴う亀裂等の虞もない。特に、第２弯曲壁部23及び第１弯曲壁部21によって、弾性的に柔軟に変形して無理な力（応力）が、連結部位Ｅに発生するのを緩和している。
また、第１弯曲壁部21の基端部21ｂは肉厚でコシが強く、連結部位Ｅがくの字状に屈曲するのを防止する。連結壁部20に発生する応力が均一化され、応力集中の発生が緩和される。 As shown in FIGS. 4 and 5, during operation of the pump, the connection portion E between the drive shaft portion 30 and the connection wall portion 20 is not suddenly bent, and stress concentration is reduced. . That is, as shown in FIG. 8 showing the conventional example and FIG. 5 and FIG. 4 showing the present invention, the connecting wall portion 20 is elastically bent into an overall S-shape without being extremely bent. There is no possibility of deformation and stress concentration, and there is no risk of cracks associated with fatigue. In particular, the second bent wall portion 23 and the first bent wall portion 21 alleviate the generation of an unreasonable force (stress) in the connecting portion E by being elastically and flexibly deformed.
Further, the base end portion 21b of the first bent wall portion 21 is thick and strong, and prevents the connecting portion E from bending in a dogleg shape. The stress generated in the connecting wall portion 20 is made uniform, and the occurrence of stress concentration is mitigated.

図７と図８に示した従来のダイヤフラム９を有するダイヤフラム集合体90は、連続使用で１５０時間で亀裂等の損傷が確認された。これに対して図１と図５に示したダイヤフラム３を有するダイヤフラム集合体13は、４５０時間以上でも損傷が確認できず、連続使用時間が３倍以上（４５０時間以上）延びたのを確認できた。 In the diaphragm assembly 90 having the conventional diaphragm 9 shown in FIGS. 7 and 8, damage such as cracks was confirmed in 150 hours after continuous use. On the other hand, the diaphragm assembly 13 having the diaphragm 3 shown in FIGS. 1 and 5 could not be damaged even after 450 hours or more, and it could be confirmed that the continuous use time was extended three times or more (450 hours or more). It was.

以上のように、本発明のダイヤフラムは、縮小と拡大が繰り返されるポンプ室１の一部を形成する円筒壁部10と、自由状態で円筒壁部10に同軸心状に配設されると共にポンプ室１を縮小・拡大させるための駆動軸部30と、円筒壁部10と駆動軸部30と連結する連結壁部20とを、一体成型したダイヤフラムに於て、連結壁部20は、自由状態で、駆動軸部30の一端面32の周縁部32ａから軸心一方向Ｎ１に突出しつつラジアル外方向へ弯曲する第１弯曲壁部21と、軸心直交状の平面状壁部22と、ラジアル外方に延伸しつつ軸心一方向Ｎ１に弯曲して円筒壁部10に連続する第２弯曲壁部23とを、一体連続状に有する横断面Ｓ字状に形成されているので、ポンプ室１を拡大・圧縮する際に、駆動軸部30と連結壁部20の接続部位Ｅに、応力集中が発生するのを緩和して、亀裂等の損傷を防止できる。耐久性が向上し、長期間にわたって使用できる（長寿命化できる）。特に、小さいケーシング内部空間に収納する必要があるダイヤフラムは、変形する壁部（膜部）が薄肉に形成されるため、従来では、応力集中が発生して損傷していたが、本発明によって応力集中が緩和されて、壁部を薄肉に形成しても十分な耐久性を得ることができ、特に、小型の流体用ダイヤフラムポンプに最適である。 As described above, the diaphragm of the present invention includes the cylindrical wall portion 10 that forms a part of the pump chamber 1 that is repeatedly reduced and enlarged, and is disposed coaxially with the cylindrical wall portion 10 in a free state and pumped. A diaphragm in which a drive shaft 30 for reducing and enlarging the chamber 1 and a connecting wall 20 connected to the cylindrical wall 10 and the drive shaft 30 are integrally molded. The connecting wall 20 is in a free state. Thus, a first bent wall portion 21 that curves in a radially outward direction while projecting in one axial center direction N1 from the peripheral edge portion 32a of the one end surface 32 of the drive shaft portion 30, a planar wall portion 22 orthogonal to the axial center, and a radial The pump chamber is formed in an S-shaped cross section having a second curved wall portion 23 that extends outward and is bent in one axial center direction N1 and continuous with the cylindrical wall portion 10. When expanding and compressing 1, the stress concentration is reduced at the connection part E between the drive shaft 30 and the connecting wall 20. Damage such as cracks can be prevented. Durability is improved and can be used for a long time (long life). In particular, a diaphragm that needs to be housed in a small casing internal space is formed with a thin wall portion (film portion) to be deformed, and thus has conventionally been damaged due to stress concentration. Concentration is alleviated and sufficient durability can be obtained even if the wall is formed thin, and is particularly suitable for a small diaphragm pump for fluid.

また、連結壁部20の第１弯曲壁部21が、駆動軸部30の一端面32に接近するにつれて、肉厚寸法ｔがしだいに増加するように形成されているので、第１弯曲壁部21の基端部21ｂ側のコシを強くすると共に、平面状壁部22及び第２弯曲壁部23側を撓みやすくして、連結部位Ｅに応力集中が発生するような無理な力（応力）を発生させず亀裂等の破損を防止できる。さらに、連結壁部20にかかる応力を均一状にして応力集中や繰り返し荷重（疲労）による亀裂等の破損を防止できる。 In addition, since the first curved wall portion 21 of the connecting wall portion 20 is formed so that the wall thickness t gradually increases as it approaches the one end surface 32 of the drive shaft portion 30, the first curved wall portion is formed. Unreasonable force (stress) that strengthens the stiffness on the base end 21b side of the 21 and makes the flat wall portion 22 and the second curved wall portion 23 side bend easily so that stress concentration occurs at the connecting portion E. It is possible to prevent breakage such as cracks without generating a crack. Furthermore, the stress applied to the connecting wall portion 20 can be made uniform to prevent breakage such as cracks due to stress concentration or repeated load (fatigue).

また、円筒壁部10の内径寸法をＤ₁₀、駆動軸部30の一端面32の外径寸法をｄとすると、０．４５・Ｄ₁₀≦ｄ≦０．６０・Ｄ₁₀なる数式が成立するように、駆動軸部30の外径寸法を小さく設定したので、駆動軸部30が受ける外力を、円滑に第１弯曲壁部21や第２弯曲壁部23へ伝達して、局部的に無理な（過大な）応力を発生させず、ダイヤフラム３の寿命を延ばすことができる。また、第１弯曲壁部21や第２弯曲壁部23を十分に弾性変形可能に形成でき、応力集中を緩和できる。 When the inner diameter dimension of the cylindrical wall portion 10 is D ₁₀ and the outer diameter dimension of the one end surface 32 of the drive shaft portion 30 is d, the following equation is established: 0.45 · D ₁₀ ≦ d ≦ 0.60 · D ₁₀ As described above, since the outer diameter of the drive shaft portion 30 is set to be small, the external force received by the drive shaft portion 30 is smoothly transmitted to the first bent wall portion 21 and the second bent wall portion 23 to be locally impossible. The life of the diaphragm 3 can be extended without generating excessive (excessive) stress. Further, the first bent wall portion 21 and the second bent wall portion 23 can be formed to be sufficiently elastically deformable, and stress concentration can be reduced.

１ポンプ室
10 円筒壁部
20 連結壁部
21 第１弯曲壁部
22 平面状壁部
23 第２弯曲壁部
30 駆動軸部
32 一端面
32ａ周縁部
Ｄ₁₀ 内径寸法
ｄ外径寸法
Ｎ１軸心一方向
ｔ肉厚寸法 1 Pump room
10 Cylindrical wall
20 Connecting wall
21 1st wall
22 Planar wall
23 Second Folding Wall
30 Drive shaft
32 One end
32a Perimeter D ₁₀ Inner diameter d Outer diameter N1 One axial direction t Thickness

Claims

縮小と拡大が繰り返されるポンプ室（１）の一部を形成する円筒壁部（10）と、自由状態で該円筒壁部（10）に同軸心状に配設されると共に上記ポンプ室（１）を縮小・拡大させるための駆動軸部（30）と、上記円筒壁部（10）と上記駆動軸部（30）と連結する連結壁部（20）とを、一体成型したダイヤフラムに於て、
上記連結壁部（20）は、自由状態で、上記駆動軸部（30）の一端面（32）の周縁部（32ａ）から軸心一方向（Ｎ１）に突出しつつラジアル外方向へ弯曲する第１弯曲壁部（21）と、軸心直交状の平面状壁部（22）と、ラジアル外方に延伸しつつ上記軸心一方向（Ｎ１）に弯曲して上記円筒壁部（10）に連続する第２弯曲壁部（23）とを、一体連続状に有する横断面Ｓ字状に形成され、上記連結壁部（20）の上記第１弯曲壁部（21）が、上記駆動軸部（30）の上記一端面（32）に接近するにつれて、肉厚寸法（ｔ）がしだいに増加するように形成されていることを特徴とするダイヤフラム。 A cylindrical wall portion (10) that forms a part of the pump chamber (1) that is repeatedly reduced and enlarged, and the pump chamber (1) that is coaxially disposed on the cylindrical wall portion (10) in a free state. A diaphragm in which a drive shaft portion (30) for reducing and enlarging a), a cylindrical wall portion (10), and a connecting wall portion (20) connected to the drive shaft portion (30) are integrally molded. ,
The connecting wall portion (20) is bent in a radially outward direction while protruding in one axial direction (N1) from the peripheral edge portion (32a) of the one end face (32) of the drive shaft portion (30) in a free state. 1 curved wall portion (21), planar wall portion (22) orthogonal to the axial center, and curved in the axial direction (N1) while extending radially outward to the cylindrical wall portion (10). A continuous second curved wall portion (23) is formed in an S-shaped transverse cross section, and the first curved wall portion (21) of the connecting wall portion (20) is the drive shaft portion. A diaphragm characterized in that the thickness (t) gradually increases as it approaches the one end face (32) of (30) .

上記円筒壁部（10）の内径寸法を（Ｄ ₁₀ ）、上記駆動軸部（30）の上記一端面（32）の外径寸法を（ｄ）とすると、０．４５・Ｄ ₁₀ ≦ｄ≦０．６０・Ｄ ₁₀ なる数式が成立するように、上記駆動軸部（30）の上記外径寸法を小さく設定した請求項１記載のダイヤフラム。 When the inner diameter dimension of the cylindrical wall portion (10) is (D ₁₀ ) and the outer diameter dimension of the one end face (32) of the drive shaft portion (30) is (d), 0.45 · D ₁₀ ≦ d ≦ The diaphragm according to claim 1, wherein the outer diameter dimension of the drive shaft portion (30) is set to be small so that a mathematical expression of 0.60 · D ₁₀ is established .