200918792 九、發明說明： 【發明所屬之技術領域】 本發明係有關於密封構造體。 【先前技術】 在半導體製造裝置或液晶製造裝置中，有是將石英或陶瓷 和不銹鋼等的金屬材組合使用的部位，而此種部位的密封構 造，自以往就大多是使用橡膠密封。 ，其理由為’由於石英或喊料破裂（脆），所以選定容易 弹性變形的橡膠材質是適當的。 % 然而，在近年來的半導體或液晶_絲置巾，正在高精 =、南機能化，就以往的橡膠㈣來說，在透氣性、耐熱性、 而…漿性、对自由基性及壽命方面，漸漸有無法對應的情況。 於是提案在此料性上優越的使用了金屬材質之金 (metal)密封（例如，參照專利文獻丄）。 ί】日本專利特開2 ° ° 2—3 1 7 8 8 9號公報 封相金屬（metai)密封的密封構造體中，金屬密 數大(高)的金屬=緣= Π等之緊固外力和應變及其變動而使石以、 碭。再者，上述專利文獻1去跄、电田认知，」开0緣贩裂的問 但以第5圖所例示那樣的大型二（m接頭的部位， 4〇而言，熱變形（熱應㈤、^尺(寸n的板狀脆性構件 緊固力ϊ造成的外力應變等亦=過==變更;螺栓 的製3置在於提供一種在運用於:導體ϊ液晶 m之石夬（或陶幻和金屬的所謂線膨=== 200918792 2個構件間具優越密舰（密封） 環亦能維持高密封性能，且由就异疋反覆的熱循 不致於破裂之壽命長的密封或喊）所成的對象構件 大的第1金屬平坦ί部及第數比上述低線膨脹係數還 設在用以區劃形成密封空;屬 構件以從上㈣，將上述脆性 離狀態下予以挾設保持。 第2金屬平坦面部回彈地遊 緣部又以用外 :透過介設在用以區劃形成密 ^上述外緣部的-面之f摘主㈣、以及介設在上述第2金 件的另一面之間的副密封，將上述脆性構 狀態下予以挾設保^ 、第2金屬平坦面部回彈地遊離 形的:屬ii主密封及副密封係以金屬為主材之可壓縮彈性變 述副i封==== =，上述主密封和上述副密封之外形形狀及外形尺寸設定 成相同。 依據本發明，可獲得如次的顯著效果。 石英，陶瓷的脆性構件係在線膨脹係數不同的第i金屬平 ί面ϊ、第2金屬平坦面部之間以回彈地遊離狀態被挾設保 、，第1、第2金屬平坦面部的熱變形（熱應變）、螺栓緊固造 成之外力變形、以及加工精度上的形狀尺寸誤差造成的影響等 200918792 脆性構件，即使反覆熱循環，也可長期間發揮優 越的後封性能。而且能防止脆性構件的破裂。藉此 = 體或液晶之製造裝置的高性能化及高機能化有^ 爭 步來说’係能_較簡單的構成，對紐構件 止難以進行的金屬密封（metal seal)。 戰至目則為 【實施方式】 以下，根據圖示之實施形態詳述本發明。 在第1圖和第4圖之-實施形態中，i是由 紐。該祕婦1讀密^用^ 2=屬ii 2 低線膨脹係數還大的線膨脹係 屬千坦面部11和第2金屬平坦面部12被（間接地） 接著’帛1圖是簡略的要部剖面圖，第 於本發明^咖遍錄是域為G.5xlG361=—6圖， 此外，石英的線膨脹係數是〇 5x10—6。 ,正方形、六角形或橢圓等，豆形妝右久 ί二觸造裝置或液晶製造= 二緊: 壓構件7與第丄金屬平 子形，剖面推 屬是 藉由2片間隔件4、5 = 環狀推壓構件7係 10是主耗並彻螺栓8翻接於外殼本體6。 鮮板狀r性播^丨设於外殼本體6的第1金屬平坦面部u :、:板狀脆性構件工的外 主密封1G係區劃形成密封空間2的密封）13之間。该 200918792 同^主密封10係以第3 (A)圖、第3 (B)圖或第3 (c) 圖所^，的金屬為主材之可_彈性變形的金屬密封。 ^疋細密封（輔助密封），其介設於推麵件 »===:件1的外緣部1 A"另-面(上面)200918792 IX. Description of the Invention: TECHNICAL FIELD OF THE INVENTION The present invention relates to a sealed structure. [Prior Art] In a semiconductor manufacturing apparatus or a liquid crystal manufacturing apparatus, a metal or a metal material such as a ceramic or a stainless steel is used in combination, and a sealing structure of such a portion is often a rubber seal. The reason is that the rubber material which is easily elastically deformed is suitable because the quartz or the shattering material is broken (brittle). % However, in recent years, semiconductors or liquid crystal ray towels are being refined in high precision and in the south. In terms of rubber (four), in terms of gas permeability, heat resistance, ..., pulpiness, free radicality and longevity On the other hand, there are gradually cases where it is impossible to respond. Therefore, it has been proposed to use a metallic metal seal in this material (for example, refer to the patent document 丄). 】]Japanese Patent Laid-Open No. 2 ° ° 2—3 1 7 8 8 9 In the sealing structure of a sealed metal (metai) seal, the metal with a large number of (high) metal = edge = 紧固, etc. And the strain and its changes make the stone, 砀. In addition, the above-mentioned Patent Document 1 goes to the sputum and the electric field to recognize, and the problem is that the large-scale two (m-joint portion, 4 ,, heat deformation (heat should be exemplified in Fig. 5) (5), ^ ruler (the external force strain caused by the tightening force of the plate-shaped brittle member of the inch n is also = = = change; the 3 set of the bolt is provided to provide a type of stone used in the conductor: liquid crystal m (or pottery) The so-called line expansion of illusion and metal === 200918792 The superior hull (sealing) between the two components can also maintain a high sealing performance, and the long-lasting seal or shouting by the heat that is repeated without rupture) The first metal flat portion and the third ratio of the target member are larger than the low linear expansion coefficient to form a seal space, and the member is held in the brittle state from above (4). The second metal flat surface rebounds from the edge portion of the second metal piece to the outer surface of the outer surface portion of the outer edge portion, and the other is disposed on the second metal piece. The sub-sealing between the one side is set in the above-mentioned brittle structure, and the second metal flat surface is rebounded. The shape of the ground is free: the main seal of the ii main seal and the sub-sealing system are made of a metal-based compressive elastic deformation sub-i seal =====, and the shape and outer shape of the main seal and the sub-seal are set to be the same. According to the present invention, a remarkable effect can be obtained. The brittle member of quartz and ceramic is protected by the i-th metal flat surface having different linear expansion coefficients and the second metal flat surface in a rebound free state. , thermal deformation (thermal strain) of the first and second metal flat faces, external force deformation caused by bolt fastening, and influence of shape and size error in machining accuracy, etc. 200918792 Brittle member can be used for a long period of time even if the thermal cycle is repeated It can provide excellent post-sealing performance and prevent cracking of brittle components. This means that the high-performance and high-performance of the manufacturing equipment of the body or liquid crystal has a tendency to make a simpler structure. The metal seal is difficult to carry out. [Embodiment] Hereinafter, the present invention will be described in detail based on the embodiments shown in the drawings. In the first embodiment and the fourth embodiment, i is New Zealand. The secretive woman reads 1 密^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ In the main part of the present invention, the field is G.5xlG361=-6, and the linear expansion coefficient of quartz is 〇5x10-6. Square, hexagon or ellipse, etc. Right long-twisting device or liquid crystal manufacturing = two tightness: the pressing member 7 and the second metal flat shape, the cross-section is pushed by the two spacers 4, 5 = the annular pressing member 7 is the main consumption The bolt 8 is turned over to the outer casing body 6. The fresh plate-shaped r-shaped broadcast is provided on the first metal flat surface portion u of the outer casing main body 6 : the outer main seal 1G of the plate-shaped brittle member is partitioned to form the sealed space 2 Sealed between 13). The 200918792 and the main seal 10 are metal-based elastically deformable metal seals of the third (A), third (B) or third (c) drawings. ^疋fine seal (auxiliary seal), which is placed on the pusher part »===: the outer edge part of the piece 1 A" another side (top)
辅助密封）20係以第3⑷圖、第3 (B) :屬：?)圖所例示那樣的金屬為主材之可厂卿性J 1、ΐί全ίί二34Γ2Τΐ楚了解，脆性構件1係從第 口彈支持力）以回彈的遊離狀態被挾設保持著。 之 器形^形^ 態。脆性構件1係容 外凸緣狀地iii;讀用外緣部(凸緣部係呈 第2圖中，在上方的（平板狀的）金屬構件15 1的外緣部（凸緣部）i A的上面之間 ：„件 密封10’該主密封10係區劃形成密封空間〖。讀的）主 又，在第2圖中、透過橫剖面L字形的金屬 與上方的金屬構件15 _湖向凹溝3 構件16 周向凹溝3内並被保持著。 卜緣。卩1 A插入於該 第1金屬平坦面部11相當於金屬構件 1〇係介設（介裝）於該第i金屬平坦面密封 上面之間且區劃形成密封空間2。 -、卜緣邛1Α的 f 2金屬平坦面部12相當於橫剖面L字形的金屬製俘拄 構件16之内方突出片部16 a的上面，副密 ^屬製保持 於該第2金屬平坦面部12與外緣部丄^的=係”設（介裝） 側對應。此外，以鏈線表示螺栓8，金屬構面===氣 16係透過該螺栓8之緊固而被連結成一體。和保持構件 由第2圖可清楚明白，脆性構件工係以從第工、第2金屬 200918792 回__狀態而被挾設保持著。 可壓轉性和副密封20都是以金屬為主材的 圖第二例如’第3(Α)圖、第3(Β) 突條tf、圖中’橫剖面呈11字狀之開口側的外侧之小 面部1卜12 ‘1圖所示）係與第1、第2金屬平坦 形，而舍〔心ΐ在第3()圖，係呈f^S字（Z字） Hr第2圖所示）從第1、第2金屬平坦面部 產生1相反^^、阳_力時’會騎賴般地扭觀形， 面壓接而形成密Γ:勢能’曲峨、18係回彈地與對象 圓山圖中’係從橫剖面矩形狀的基部突出了半 3二=19的形狀。第卜第2金屬平坦面部 生i相^ ^F那樣的力時，會像箭頭M般地扭轉變形，產 但是，密封空間2内可考量是產生負壓的情況、正壓 =、、=及負壓、正壓雙方的情況。以第lffil而言是將主密 10以其開口側朝向大氣（外部）側裝設，但是密封空曰商 二:負=情，。又’副密封20可以是與主密封1〇相同二 形狀、也可以是不同剖面形狀。亦即，例如，除了第3圖 和（A)的組合以外，也可以是第3 (A)圖和第3 πβ 之組合等。但是，第3 (Α )圖的小突條17、第二 彎曲凸部18，或第3 (C)圖的半圓山形凸部19之外 、 及外形尺寸，係以主密封ίο和副密封20中設定成相ς乂 致相同者為宜。（此外’所謂大致相同’是指定義成如第 不般、各密封10、20的寬度尺寸W以内的尺寸差。）換古^ 係以上視圖所見兩密封1〇、20的密封線呈一致者為宜。、^，5,’The auxiliary seal) 20 is based on the 3rd (4) and 3rd (B): genus: ?) diagrams of the metal as the main material of the factory can be known as J 1, ΐί full ίί 2 34 Γ 2 Τΐ 了解 ,, the brittle member 1 is from The first bullet support force is held in the free state of the rebound. The shape of the device is ^ shape. The brittle member 1 is in the outer flange shape iii; the outer edge portion for reading (the flange portion is the outer edge portion (flange portion) of the upper (flat-plate) metal member 15 1 in the second figure. Between the top of A: „piece seal 10' The main seal 10 is divided to form a sealed space 〖. Read the main, in the second figure, through the cross-section L-shaped metal and the upper metal member 15 _ lake direction The groove 3 member 16 is held in the circumferential groove 3. The rim 1A is inserted into the first metal flat surface portion 11. The metal member 1 is interposed (intermediate) to the ith metal flat surface. The upper surface and the partition form a sealed space 2. The f 2 metal flat surface portion 12 of the embossed rim 1 corresponds to the upper surface of the inner protruding piece portion 16 a of the metal captive member 16 having an L-shaped cross section, and the sub-compact The system is held by the second metal flat surface portion 12 corresponding to the "system" side of the outer edge portion. Further, the bolts 8 are indicated by chain lines, and the metal facets === gas 16 are integrally joined by the fastening of the bolts 8. And holding member As is apparent from Fig. 2, the brittle member system is held in a state in which it is returned from the first work and the second metal 200918792. Both the compressible property and the sub-sealing 20 are mainly metal-based, and the second, for example, the 'third (Α) map, the third (Β) ridge tf, and the cross-section of the cross-section of the cross-section of the figure 11 The outer small face 1 Bu 12 '1 is shown in the figure) and the first and second metals are flat, and the heart is in the 3rd (3), which is f^S (Z) Hr 2 It is shown that when the 1st and 2nd metal flat faces are generated, 1 is opposite to the ^^, _ force, 'they will be twisted and twisted, and the surface will be crimped to form a close: the potential energy is curved, and the 18 series is rebounded. In the object circle diagram, the shape of the rectangle from the rectangular cross section of the cross section protrudes by a half 3=19. When the force of the second metal flat surface is the same as that of the arrow M, the deformation is caused by the arrow M. However, in the sealed space 2, it is considered that negative pressure is generated, positive pressure =, , = and The situation of both negative pressure and positive pressure. In the case of the lffil, the main seal 10 is installed with the open side facing the atmosphere (outside) side, but the seal is empty. Further, the sub-sealing 20 may have the same shape as the main seal 1 or may have a different cross-sectional shape. That is, for example, in addition to the combination of Fig. 3 and (A), a combination of the third (A) map and the third πβ may be used. However, the small ridge 17 of the third (Α) diagram, the second curved convex portion 18, or the semi-circular mountain-shaped convex portion 19 of the third (C) diagram, and the outer dimensions are the main seal ίο and the sub-sealing 20 It is advisable to set the same to the same. (In addition, the term "substantially the same" means that the difference in size between the widths W and W of each of the seals 10 and 20 is defined as the first step.) For the above view, the seal lines of the two seals 1 and 20 are identical. should. ,^,5,’
田J 200918792 岔封20因為是輔助用的，所以並不太需要密封性能，可省略 別的表面被覆或加工。亦即主密封1〇係就防接觸用途，用 以賦與接著性等之表面被覆層而形成銀、金、鎳、銅、鋼等之 電鍍層，亦可包覆形成p T F E等之樹脂被覆層。相對地， 副密封20因為不直接接觸密封空間2内的流體，所以基於 面等來考量，將該等予以省略是適當的。 、+ 又，作為主密封1〇、副密封2〇的基底金屬材料， 不銹鋼、鎳合金或鐵合金（A286等）。 口‘ 此外’除了第3圖所例示的以外，亦有是使用金屬〇形 金屬C形環或金屬板製波形環等不錯的情況。 ^次，進^了第4圖和第6圖所示本發明實施例、與第5 圖和第6圖所示習知例之密封性能的比較試驗。亦即，^ 實施例（第4圖）和習知例（第5圖）之不同點在於是否 副J封2〇。密封1〇、2〇係與第3 (幻圖所述及者形狀相同， 且欲封母材設為SUS630，並於其上鍍有3〇〜5〇卿的銀。而 脆性構件1是使科板狀的^英材改賴隔件5的厚度， 口例（第5圖）中’推壓構件7直接賴性構件4()麵並 固疋者0 &經過比較第5圖之習知例的密封性能與第4圖之本發明 (實施9品）的密封性能並進行試驗之後，以往H e的漏洩 =二xlO〜lxl〇10pa.m3/sec左右，但以本發明實施品 =’ He的漏茂量則是大大地改善成為1χ1〇—llpa.m3/sec 、S ”及。此外，其係在密封空間保持成真空（負壓）且100。^ 的熱循環試驗中所計測到的值。 +田上，效針對在第4 ®和第5騎生大的密雌能差異 之理由考察後，發現有如下的情況。 (1)推壓構件7存在原來的應變或形狀尺寸誤差，在那情 習知例（第5圖）而言’係對該應變或形狀尺寸誤差所 直接接觸的部位之板狀脆性構件4〇上造成影響而使該板狀脆 200918792 性構件40產生應變（變形），在主密封1〇全周上產生不 抵接而使密封性能惡化。相對地，以本發明實施品 、 來說’可認為是推麗構件7原有的應變或形狀 ； 封（辅助密封）20户斤緩和（緩衝），主密封1〇乃^及^: J象=等，抵接(接觸）’而顯現出整體的密封性能優^的社 果。，被封（輔助密封）20亦可說是扮演所謂緩衝材之角色： 起第1 件1、4G是石英或喊，而其線膨脹係數比 =^、第2金屬平坦面部U、12還低（小），所以隨著低⑽ ΐΐί度變化（熱變化）而相對地在脆性構件40和第t 部n、12之間產生應變或（相對）變動，而且， f累仏8的對應位置和從那離開的位置，相對的變形Tian J 200918792 岔 20 20 Because it is auxiliary, it does not require sealing performance, and other surface coating or processing can be omitted. In other words, the main seal 1 is used for contact prevention, and is used to form a plating layer of silver, gold, nickel, copper, steel, etc., or a resin coating of p TFE or the like. Floor. On the other hand, since the sub-sealing 20 does not directly contact the fluid in the sealed space 2, it is appropriate to omit it based on the surface or the like. +, as the base metal material of the primary seal 1〇 and the secondary seal 2〇, stainless steel, nickel alloy or iron alloy (A286, etc.). In addition to the illustrations shown in Fig. 3, the mouth ‘in addition’ is also a good case of using a metal 〇-shaped metal C-ring or a corrugated metal plate. ^, the comparative test of the sealing performance of the embodiment of the present invention shown in Figs. 4 and 6 and the conventional examples shown in Figs. 5 and 6 is carried out. That is, the difference between the embodiment (Fig. 4) and the conventional example (Fig. 5) is whether or not the sub-J is 2 〇. The sealed 1〇, 2〇 series and the 3rd (the same as the shape described in the magical figure, and the base material to be sealed is set to SUS630, and the silver of 3〇~5〇 is plated thereon. The brittle member 1 is made The thickness of the plate is changed to the thickness of the spacer 5, and in the case (Fig. 5), the pressing member 7 is directly attached to the member 4 () and is fixed. 0 & After the sealing performance of the example and the sealing performance of the invention of the present invention (Fig. 4) are tested and tested, the leakage of the conventional He is about two xlO~lxl 〇10 pa.m3/sec, but the embodiment of the present invention = 'The leakage amount of He is greatly improved to 1χ1〇-llpa.m3/sec, S ” and. In addition, it is measured in a thermal cycle test in which the sealed space is kept vacuum (negative pressure) and 100. The value of the field. + On the field, the effect was found on the reason of the difference between the 4th and the 5th riding. The following conditions were found: (1) The original strain or shape size error of the pressing member 7 In the case of the case (Fig. 5), it affects the plate-like brittle member 4 at the portion where the strain or the dimensional error directly contacts. The plate-like brittle 200918792 member 40 is strained (deformed), and the sealing performance is deteriorated over the entire circumference of the main seal 1 。. In contrast, in the embodiment of the present invention, it can be considered as a smear member. 7 original strain or shape; seal (auxiliary seal) 20 households easing (buffering), main seal 1 〇 is ^ and ^: J elephant = etc., abut (contact) and show the overall sealing performance is excellent ^ The fruit of the seal. (Auxiliary seal) 20 can also be said to play the role of so-called cushioning material: The first one, 4G is quartz or shouting, and its linear expansion coefficient ratio = ^, the second metal flat face U 12 is still low (small), so that strain (relative) changes occur between the brittle member 40 and the t-th portion n, 12 with a low (10) ΐΐ 度 degree change (thermal change), and f 仏 8 Corresponding position and relative position from the position
發生應變或變動，在習知例（第5圖）中，其鹿變或Q 變化)係在推壓構件7和脆性構件4“ = ^ 並產生於主密封1G與脆性構件4〇的一面4G 響 性能惡化。相對地，以本發明實施品（第4圖）來說& = 屬平坦面部12之間產生之相對的應變或相ί 和〔緩#η’係1妙地透過副密封（輔助密封）20而被緩 等地抵接（接2，可認為主密封10乃遍及全周對兩對象面均 r (接觸）’而示出整體的密封性能優秀的結果。副密封 (輔助畨封）20亦可說是扮演所謂緩衝材之角色。 于 接士！Γ同以上所述’本案發明所涉及的密封構造體，因為异诸 尨上述低雜脹係數還大的第1金屬平坦面部11 區ϋ，平坦面部12挟設保持，同時建構成透過介設在用以 αΪ*、封空間2的上述第1金屬平坦面部11與上述外缘When a strain or a change occurs, in the conventional example (Fig. 5, the deer change or the Q change) is applied to the pressing member 7 and the brittle member 4 " = ^ and is generated on the side of the main seal 1G and the brittle member 4 4 4G. The performance is deteriorated. In contrast, in the embodiment of the present invention (Fig. 4), & = the relative strain or phase generated between the flat faces 12 and the slow-moving #η' The auxiliary seal 20 is gently abutted (2), and the main seal 10 is considered to have r (contact) between the two surfaces over the entire circumference, and the overall sealing performance is excellent. The seal 20 can also be said to play the role of a so-called cushioning material. In the above-mentioned seal structure of the invention of the present invention, the above-mentioned first metal flat face having a large low expansion coefficient is also different. In the 11th area, the flat surface 12 is held and configured to pass through the first metal flat surface 11 and the outer edge which are interposed in the space 2*, the sealing space 2
的主密封ig、以及介設在上述第2 S 將上述構件14之_職20， M2 _也遊離狀態下予以挾設保持，所以副密封2〇 : 200918792 或熱應變並=向:== 1的密封等之脆性構件 密封用外的;.=1之被 "Z' 上述第_性構件1峨 狀態下予續郷持，密=地遊離 52:差造成的應變、熱循環等造成之熱變形二庫角變並:ί 密或封陶敝脆性軸 且外部(大氣)側的副細可在“ ^ 1 ^ ^ 200918792 【圖式簡單說明】 【巧1圖】顯示本發明之一實施形態的簡略構成說明剖面圖。 【^2圖】顯示其他實施形態之簡略構成說明剖面圖。 H3圖】顯示主密封（副密封）之各種實施例的剖面圖。 第4圖】顯示與本發明一實施形態相對應且進行 月匕f驗的裝置之要部剖面圖。 口生 圖】顯不習知例（習知品）的一例之要部的剖面圖。 圖】運用在密封性能試驗之密封的說明圖。 200918792 【主要元件符號說明】 1 脆性構件 1 A 外緣部 2 密封空間 3 周向凹溝 4、5 間隔件 6 外殼本體 7推壓構件 8 緊固用螺栓 9 大氣 10 主密封 11第1金屬平坦面部 12 第2金屬平坦面部 13 外緣部的一面 14 外緣部的另一面 15 金屬構件 16 保持構件 16a 内方突出片部 17 小突條 18 彎曲凸部 19 半圓山形突部 2 0 副密封 40 脆性構件 4 0A脆性構件的一面 14The main seal ig and the second S are disposed in the second state, and the sub-seal 2〇: 200918792 or thermal strain ==:== 1 The brittle member such as the seal is sealed; the =1 is controlled by the above-mentioned _th member in the state of 1 峨, and the density is 52: the strain caused by the difference, the thermal cycle, etc. The thermal deformation of the two reservoir angles is changed: ί dense or sealed ceramic brittle axis and the outer (atmospheric) side of the sub-fine can be in " ^ 1 ^ ^ 200918792 [schematic description] [Choose 1] shows one implementation of the present invention BRIEF DESCRIPTION OF THE DRAWINGS FIG. 2 is a cross-sectional view showing a simplified configuration of another embodiment. FIG. 3 is a cross-sectional view showing various embodiments of a main seal (sub-sealing). FIG. 4 is a view showing the present invention. A cross-sectional view of an essential part of a device that corresponds to an embodiment and is subjected to a monthly test. Fig. 3 is a cross-sectional view of an essential part of an example of a conventional example (a conventional product). Explanatory diagram 200918792 [Explanation of main component symbols] 1 Brittle component 1 A Edge portion 2 sealed space 3 circumferential groove 4, 5 spacer 6 housing body 7 pressing member 8 fastening bolt 9 atmosphere 10 main seal 11 first metal flat surface portion 12 second metal flat surface portion 13 outer side portion 14 side The other side of the rim 15 the metal member 16 the holding member 16a the inner protruding piece 17 the small ridge 18 the curved convex part 19 the semicircular mountain shaped protrusion 2 0 the secondary seal 40 the brittle member 4 0A one side of the brittle member 14