經濟部中央摞箏扃W工消費合作社印*'1私 A6 ‘二 Γ)⑽ _ϋ 五、發明説明（） <本發明背景〉 本發明有關一種插入法陰極，及其製造方法，特別是 在結構上作改良，使裝載浸漬了陰極材料的矩陣的儲存器 不需焊接到一套筒上就可固定。 —般而言，一插入法陰極可由將鬣子發射材料浸潰到 一多孔的錦燒結體而做成。自電子發射物質射出的熱離子 會經由燒結體的細孔而分散調和〇由於能得到高的射束流 密度，這樣的插入法陰極有利於大型的CRT及投射管及類 似的物品。特別是由於浸漬陰極有長的壽命期望值，所以 引起了對此技術熟知之人士的注意，打算用做高效能霣子 管的熱電子發射來源。 第1圖說明一傳統之插入法陰極。在第1圖中一多孔 的陰極矩陣1 ’在一儲存器2 ’中焊接，此儲存器2 ’由具有高 溶點的金靥如鉬（Mo)或錦（W)所做成。陰極矩陣1 ’的製作 可使一多孔的燒結體（用鎢所做並用典型的粉末治金法形 成）浸漬有如鋇（Ba)的電子放射材料。儲存器2’焊接到一 柱形套筒3’的上邊内側表面，此套筒由具由高熔點之金屬 做成並在下邊部分包含一加熱器4 ’，此加熱器作為加熱陰 極矩陣1’的熱源。 傳統的插入法陰極的製造方法如下面所述。首先，浸 漬有電子發射物質之陰極矩陣1 ’放入儲存器f内，此儲存 器隨即固定到套筒3’的上端。陰極矩陣1\儲存器2’及套 筒3 ’由電阻焊接或雷射焊接槍焊接並固定在一起。有時在 儲存器2 ’塞入套筒3 ’之前，陰極矩陣1 ’及儲存器2 ·焊接而 -3- 本紙张尺度通用中[f阐家丨_?羋（CNS)甲4規丨各（210 X 297公:^ ) 82.3. 40,000 -----------------------裝——----ir------旅 (請先閲讀背面之注意事項再場寫本頁) A6 五、發明説明（） 儲存器2 ’塞入將要焊接的套筒3 ’ 然而，傳統的插入法陰極非常難以焊接。更明確的說 ，在電阻焊接的情況下，因為儲存器及套筒由具有高熔點 的金屬做成，常常會使焊接失敗。在雷射焊接的情況下， 由於待焊接的兩値材料之間的距離必須限制在材料厚度的 10%以下，而儲存器或套筒實際上的寬度為米，這是 —値難以設定的距離。此外，在雷射焊接時，由於和儲存 器及套筒（由熔點超過2600°C的金屬做成）相比較，電子 發射材料有相對上較低之熔點（約11700 ,材料特性會 改變，或是材料可能會溶化及蒸發，導致操作特性變差。 第2圖像說明日本公開公報第62217527號所掲示的一 種可解決上面問題的插入法陰極。在第2圖中，用多孔的 鎢燒結體所做的一陰性矩陣1 (浸漬有電子發射材料）固 定在一由鉬（Ta)所做成的儲存器 2中。在陰極矩陣1的 中央，一電子發射部分la在儲存器上突出某一高度。儲存 器2^置在柱形套筒36¾上側部分，套筒3也是用飽做成 。在套筒3的内側形成4値突入内側直徑的突起Sa,儲存 器2的底部靠在此處。套筒3的上側末端向内彎曲以形成 一突綠3b,此突綠將不包括電子發射部分ia的陰極矩陣1 的邊緣圍繞。在第4圖中，參考數字 4代表装在套筒 3 内用來加熱陰極矩陣1的一加熱器。 此插入法陰極的製造方法如下面所述。陰極矩陣1固 定在儲存器2的内側表面。儲存器2自其下側部分塞入套 筒，直到到達儲存器邊牆厚度的二倍為止（自套筒頂端算 ~4~ 本紙張尺/1適用中围國\標半（CNS)甲4規格（210 X 297公货） ----------------—-----裝------訂------線- (請先《讀背面之注意事項再填寫本頁> 經濟部中央標準局工消費合作社印製 82.3. 40,000 經濟部中央標準局員工消費合作杜印製 A6 B6 五、發明説明（） 起）。套筒3的上側末端接合以形成向内錄之突綠3b,使 得插入裡面的儲存器2只向外突出陰極矩陣1的電子發射 部分la。緊接在儲存器2^部的套筒3部分在壓彎後形成 套筒内的4値突起3a〇 然而，此插入法陰極的套筒厚度很薄（約為3Θί敝米） ，所以套茼的上側末端很難蠓到90°以形成突綠。此外， 為了形成突起的壓變壓力會使包括突綠在内的套筒上側部 分變形，以致陰極矩陣不能穩定固定。此外，用來發射電 子的陰極矩陣的露出表面，由於太小以致於«子發射的效 率很低。 <發明總論> 因此本發明之一目的在於提供一可容易製造而又平穩 固定的插入法陰極。 本發明之另一目的在於提供可提升陰極矩陣電子發射 效率並降低其操作溫度之插入法陰極，因此可便一影像有 較快的輸出。 本發明之另一目的為提供製造逹成上面目的之插入法 陰極的方法。 為了逹成上述的目的，本發明之插入法陰極包含：一 加熱器，用來當作熱源；一浸漬有熱離子發射材料之陰極 矩陣，用來發射由於加熱器加熱所産生的熱離子；一套筒 ,在其上側部分接受陰極矩陣，而在下側部分則有加熱器 ，在套筒中裝有一支撑陰極矩陣的碟形支座；多數之突起 ,在套筒的内側表面以某一間隔及一預定高度形成，用來 -5- 本紙張尺度適用中國國家丨.？芈（CNS)甲4现丨各（210 X 297 H ) 82.3, 40,000 ------------------------裝------訂------^ {請先閲讀背面之注意事項再塡寫本頁> A6 經濟部t央標準居β工消費合作社印" 五、發明説明（） 支撑支座；一突綠型固定部分，在套筒的上側末端形成並 用來包圍陰極矩陣的邊緣。 製造本發明之插入法陰極的方法包含下面步驟：在套 筒的内側表面以某一間隔形成具有某一直徑之多數突起， 造些突起和套筒頂端隔有一預定之距離；插入支座，此支 座的直徑實質上相等於或略小於套筒（將由逭此突起所支 持）的内側直徑；將浸漬有電子發射材料的陰極矩陣，自 其待被支座支撑的頂部，插入套筒；將套筒的上側末端以 一預定的角度接合，以預防陰極矩陣自套筒脫落出來。 在本發明中，此陰極矩陣是由於其實體結構而並非藉 由焊接而固定到套筒上，所以在本質上就能預防由於傳統 方法的焊接熱置而導致陰極矩陣的特性改變。使用碟形支 座來取代具有傳統調和糸陰極隔電子外層的杯形儲存器， 有利於製造，而且由於質量的降低使得整體熱容量也降低 了。因此，陰性可以很快到逹操作溫度，亦即熱離子很快 開始發射，使得影像有很快的輸出時間。 <圖示的簡短說明> 參考附圖並詳加說明本發明的較佳具體實例，可更清 楚本發明的上述目的及其它優點，這些圖為·* 第1圖俗一傳統插入法陰極的橫截面圖； 第2圖像說明一傳統插入法陰極的另一具體實例的橫 截面圖； 第3圖係ί根據本發明的一插入法陰極的橫截面圖；及 第4圖俗沿箸第3圖線IV-1V所取的本發明的插入法 -6- (請先閱讀背面之注意事項再填寫本頁) i裝· 訂 線· 泰紙張尺度適用中围國家標节（CNS)甲4規格（210 X 297 fii·) 82.3. 40.000 A6 B6 經濟部中央標準局W工消費合作社印製 五、發明説明（） 陰極的截面圖。 <較佳具體實例的詳細說明> 參考第3圖及第4圖，一陰極矩陣11插入並固定於柱 形套筒的上邊内側部分，此套筒由具有高熔點的金靥如鎌 (W )、館（Mo)或飽（Ta)所做成。在套筒13的下側部分設有 一加熱器14。陰極矩陣11經製造後可使由傳統粉末治金法 所做的多孔錦燒結體會浸漬有如鋇（Ba)、鈣（Ca)之類的電 子發射材料。陰極矩陣11的上側邊綠做成圓形並具有一預 定之曲度。在某些情形中，陰極矩陣11的上側邊緣可以某 一角度傾向陰極矩陣的中心。此處傾斜角小於45度較佳。 為了預防陰極矩陣脱落，在套筒13上形成一突緣型固定部 分13b ,此部分有相對應於陰極矩陣11的上側邊綠。由第 4圖可以看出至少有3値突起13a在内側直徑處形成，這些 突起有相同之間隔並且和套筒13的上側末端隔有某一間距 。在陰極矩陣11的底部處裝有一碟形支座12,做為支撑裝 置並且和陰極矩陣相接觸。碟形支座12藉由突起13a支撑 其周圍而可以固定到套筒13内。支座12的直徑最好的實質 上和套筒13的内側直徑相同或略小於套筒之内側直徑，而 且支座的厚度愈薄愈好。第3圖中未描述的黎考數字lla 代表陰極矩陣11的電子發射表面。在第4圖中，省略了加 熱器14的說明。 現在將在下面說明本發明之插入法陰極的製造方法。 在套筒13内至少形成3個突出的突起13a,這些突起在套筒 的内側直徑形成並且彼此間隔相等，而且距套筒頂端有某 -7- {請先閲讀背面之注意事項再項寫本頁} -丨裝， 訂. 線 本紙張尺度適用中围國家桴準（CNS)甲4峴恪〔210 X 237公货） 82.3. 40,000 09⑹ 09⑹ 經濟部中央標準曷B工消費合作社印®ί A6 B6 五、發明説明（） 一距離，此距離至少要等於陰極矩陣11的高度。碟形支座 12 (其直徑實質上相等於或是略小於套筒13的内側直徑 )自套筒頂端插入套筒並且由突起13a所支撑。浸漬有電 子發射材料的陰極矩陣11隨即自相同方向（支座120?支撑 的方向）插入套筒13。然後套筒13的上側末端對應於陰極 矩陣11的上側邊緣接合，形成突緣型固定部分13b。這可 以預防陰極矩陣11自套筒13的頂端脱落。 在根據本發明的製造方法所製造出來的插入法陰極中 ，陰極矩陣11及支座12是由於其實體結構而非由焊接來固 定在套筒上，固此在本質上可預防由於焊接時要加熱所引 起的陰極矩陣特性變化。特別是由於突起 13a及套筒13 在預先就已形成，在支座12及陰極矩陣11裝好後接箸就形 成插入固定部分13b,所以和傳統方法不同，並不會發生 套筒的周圍會變形。 套筒13不會變形有利於陰極矩陣11穩定固定在套筒11 上。使用沒有隔電子外層的碟形支座12來取代傳統插入法 陰極的杯形儲存器，有利於製造，而且由於質量減少了， 所以整體的熱容量也降低了。熱容置的降低會使陰極快速 到逹其操作溫度，結果使影像輸出更快速。陰極矩陣11的 圓形上側邊緣有利於陰極矩陣的燒結及套筒13的固定部分 13b的形成。此外，陰極矩陣11的廣大電子發射表面11a 大幅增加電子發射效率。 雖然藉由參考本發明的較佳具體實例，對本發明特別 的加以說明及描述，但是對此技藝熟知者須明白對於本發 -8- --------------------------裝------tr------線------1 (請先《讀背面之注意事項再填寫本頁) 本纸張又度通用中HS家標苹（CNS)甲4規格（210 X Μ7公皆） 82.3. 40,〇〇〇 2〇9ϋυ Α6Β6 五、發明説明（） 明在形式及細節上做不同之改變並不會俘離如附加申請專 利範圍中所界定的本發明之精神及範圍。 (請先閱讀背面之注意事項再填寫本頁) 經濟部中央標準局男工消费合作社印5衣 -9 — 本紙張尺度適用中國国家漂準（CNS〉甲4規格（210 X 297 W釐） 82.3. 40,000Printed by the Central Government of the Ministry of Economic Affairs, Zhengzong W Industrial Consumer Cooperative ** 1private A6 '2Γ) ⑽ _ϋ 5. Description of the invention () < Background of the invention> The present invention relates to an insert cathode and its manufacturing method, especially in The structure is modified so that the reservoir loaded with the matrix impregnated with the cathode material can be fixed without welding to a sleeve. Generally speaking, an intercalation cathode can be made by impregnating a hyaline emitting material into a porous brocade sintered body. Thermionic ions emitted from the electron-emitting substance are dispersed and reconciled through the pores of the sintered body. Since a high beam current density can be obtained, such an insertion cathode is advantageous for large-scale CRTs, projection tubes, and the like. In particular, due to the long life expectancy of impregnated cathodes, it has attracted the attention of those skilled in the art and is intended to be used as a source of thermal electron emission for high-efficiency booze tubes. Fig. 1 illustrates a conventional insertion cathode. In Fig. 1, a porous cathode matrix 1 'is welded in a reservoir 2' made of gold with high melting point such as molybdenum (Mo) or bromine (W). The manufacture of the cathode matrix 1 'allows a porous sintered body (made of tungsten and formed by a typical powder metallurgy method) to be impregnated with an electron-emitting material such as barium (Ba). The reservoir 2 'is welded to the upper inner surface of a cylindrical sleeve 3', which is made of a metal with a high melting point and contains a heater 4 'at the lower part, which serves as a heating cathode matrix 1' Heat source. The manufacturing method of the conventional insertion cathode is as follows. First, the cathode matrix 1 'impregnated with the electron-emitting substance is placed in the reservoir f, which is then fixed to the upper end of the sleeve 3'. The cathode matrix 1 \ reservoir 2 'and the sleeve 3' are welded and fixed together by resistance welding or laser welding gun. Sometimes before the storage 2 'is inserted into the sleeve 3', the cathode matrix 1 'and the storage 2 are welded. The standard of this paper is universal. [F 解 家 丨 _? 芈 （CNS) A 4 regulations 丨 Each (210 X 297 male: ^) 82.3. 40,000 ----------------------- installed -------- ir ------ brigade ( Please read the precautions on the back before writing this page) A6 V. Description of the invention () The storage 2 'plugs into the sleeve 3 to be welded' However, the traditional insertion cathode is very difficult to weld. More specifically, in the case of resistance welding, because the reservoir and the sleeve are made of a metal with a high melting point, the welding often fails. In the case of laser welding, because the distance between the two materials to be welded must be limited to less than 10% of the thickness of the material, and the actual width of the reservoir or sleeve is meters, this is-difficult to set the distance . In addition, during laser welding, the electron-emitting material has a relatively low melting point (approximately 11700, the material properties will change, as compared with the reservoir and the sleeve (made of metal with a melting point exceeding 2600 ° C)) It is because the material may melt and evaporate, resulting in poor operating characteristics. The second image illustrates an insertion method cathode that can solve the above problem shown in Japanese Laid-Open Patent No. 62217527. In FIG. 2, a porous tungsten sintered body is used A negative matrix 1 (impregnated with electron-emitting material) is fixed in a reservoir 2 made of molybdenum (Ta). In the center of the cathode matrix 1, an electron-emitting portion la protrudes from the reservoir by a certain amount Height. The reservoir 2 is placed on the upper part of the cylindrical sleeve 36¾, and the sleeve 3 is also made of saturated material. On the inside of the sleeve 3, a protrusion Sa with a value of 4 that protrudes into the inside diameter is formed, and the bottom of the reservoir 2 rests here The upper end of the sleeve 3 is bent inward to form a protruding green 3b, which surrounds the edge of the cathode matrix 1 excluding the electron emitting portion ia. In the fourth figure, reference numeral 4 represents the sleeve 3 Used to heat the cathode matrix 1 Heater. The manufacturing method of this insertion cathode is described below. The cathode matrix 1 is fixed to the inner surface of the reservoir 2. The reservoir 2 is inserted into the sleeve from its lower part until it reaches twice the thickness of the reservoir side wall Up to (counting from the top of the sleeve ~ 4 ~ This paper ruler / 1 applies to the Zhongwei National Standards (CNS) A4 specifications (210 X 297 public goods) --------------- -------- installed ------ ordered ------ line- (please read "Notes on the back and then fill out this page"> Printed by the Industrial and Consumer Cooperative of the Central Bureau of Standards of the Ministry of Economy 82.3. 40,000 A6 B6 printed by the Consumer Standards Cooperation Department of the Ministry of Economic Affairs of the Ministry of Economic Affairs 5. The description of the invention (from). The upper end of the sleeve 3 is joined to form the inwardly projecting green 3b, so that the storage 2 inserted inside is only outward The electron emission portion la of the cathode matrix 1 is protruded. The portion of the sleeve 3 next to the reservoir 2 ^ portion is formed into a 4 protrusion 3a in the sleeve after being bent. However, the thickness of the sleeve of this insertion method cathode is very thin ( (About 3Θί 敝 米), so the upper end of the sheath is difficult to midge to 90 ° to form a protruding green. In addition, the pressure change pressure to form the protruding will include the protruding green The upper part of the sleeve is deformed so that the cathode matrix cannot be stably fixed. In addition, the exposed surface of the cathode matrix used to emit electrons is too small to have a low efficiency of sub-emission. ≪ Overview of the Invention > One object is to provide an insertion cathode that can be easily manufactured and is stably fixed. Another object of the present invention is to provide an insertion cathode that can improve the electron emission efficiency of the cathode matrix and lower its operating temperature, so that the image can be faster Another object of the present invention is to provide a method of manufacturing an insert cathode that achieves the above purpose. For the purpose described above, the insert cathode of the present invention includes: a heater used as a heat source; an impregnation Cathode matrix with thermionic emission material, used to emit hot ions generated by heater heating; a sleeve, which receives the cathode matrix on the upper part, and a heater on the lower part, with a support in the sleeve Cathode matrix disk-shaped support; most of the protrusions are formed at a certain interval and a predetermined height on the inner surface of the sleeve, used to -5- This paper standard is suitable for Chinese countries芈 (CNS) A 4 is now 丨 each (210 X 297 H) 82.3, 40,000 ------------------------ installed ------ ordered ------ ^ {Please read the precautions on the back first and then write this page> A6 Printed by the Ministry of Economic Affairs, Standard Home, and β Industry and Consumer Cooperatives Co., Ltd. " V. Description of the invention () Supporting support; a sudden green type The fixed portion is formed at the upper end of the sleeve and used to surround the edge of the cathode matrix. The method for manufacturing the insert cathode of the present invention includes the following steps: forming a plurality of protrusions with a certain diameter at a certain interval on the inner surface of the sleeve, making these protrusions at a predetermined distance from the top of the sleeve; inserting the support, this The diameter of the support is substantially equal to or slightly smaller than the inside diameter of the sleeve (to be supported by this protrusion); insert the cathode matrix impregnated with electron-emitting material from its top to be supported by the support, insert the sleeve The upper end of the sleeve is joined at a predetermined angle to prevent the cathode matrix from falling out of the sleeve. In the present invention, the cathode matrix is not fixed to the sleeve by welding due to its physical structure, so it can essentially prevent the characteristics of the cathode matrix from being changed due to the heat welding of the conventional method. The use of a dish-shaped support to replace the cup-shaped reservoir with the traditional harmonic cathode cathode electron-shielding outer layer is advantageous for manufacturing, and the overall heat capacity is also reduced due to the reduced quality. Therefore, the negative female can quickly reach the operating temperature, that is, the thermal ions start to emit quickly, so that the image has a fast output time. < Brief description of the drawings > With reference to the drawings and detailed description of the preferred specific examples of the present invention, the above-mentioned objects and other advantages of the present invention can be more clearly understood. The second image illustrates a cross-sectional view of another specific example of a conventional insertion cathode; FIG. 3 is a cross-sectional view of an insertion cathode according to the present invention; and FIG. 4 The insertion method of the present invention taken from the line IV-1V in Figure 3-6 (please read the precautions on the back before filling in this page) i Pack · Thread · Thai paper standard applies to the Central Standards (CNS) A 4 Specifications (210 X 297 fii ·) 82.3. 40.000 A6 B6 Printed by the Central Bureau of Standards of the Ministry of Economy W Industrial and Consumer Cooperatives V. Description of the invention () A cross-sectional view of the cathode. < Detailed description of preferred specific examples > Referring to Fig. 3 and Fig. 4, a cathode matrix 11 is inserted and fixed to the upper inner side portion of the cylindrical sleeve, which is made of gold with a high melting point such as sickle ( W), Pavilion (Mo) or full (Ta). At the lower part of the sleeve 13, a heater 14 is provided. After the cathode matrix 11 is manufactured, the porous sintered body made by the conventional powder metallurgy method can be impregnated with electron emitting materials such as barium (Ba) and calcium (Ca). The green on the upper side of the cathode matrix 11 is circular and has a predetermined curvature. In some cases, the upper edge of the cathode matrix 11 may be inclined toward the center of the cathode matrix at an angle. Here, the inclination angle is preferably less than 45 degrees. In order to prevent the cathode matrix from falling off, a flange type fixing portion 13b is formed on the sleeve 13, and this portion has a green corresponding to the upper side of the cathode matrix 11. It can be seen from FIG. 4 that at least three protrusions 13a are formed at the inner diameter, and these protrusions are spaced at the same distance from the upper end of the sleeve 13. At the bottom of the cathode matrix 11, a dish-shaped support 12 is installed as a supporting device and is in contact with the cathode matrix. The dish-shaped support 12 can be fixed into the sleeve 13 by supporting its periphery with the protrusion 13a. The diameter of the support 12 is preferably substantially the same as or slightly smaller than the inside diameter of the sleeve 13, and the thinner the thickness of the support, the better. The Leica number lla, which is not described in FIG. 3, represents the electron emission surface of the cathode matrix 11. In Fig. 4, the description of the heater 14 is omitted. The method of manufacturing the cathode of the present invention will now be explained below. At least three protruding protrusions 13a are formed in the sleeve 13, these protrusions are formed on the inner diameter of the sleeve and are equally spaced from each other, and there is a certain -7- from the top of the sleeve-{Please read the precautions on the back before writing Page}-丨 installation, ordering. The size of the line paper is suitable for Zhongwei National Standard (CNS) A 4 Xianke (210 X 237 public goods) 82.3. 40,000 09⑹ 09⑹ Central Standard of the Ministry of Economic Affairs. B6 V. Description of the invention () A distance, which must be at least equal to the height of the cathode matrix 11. The dish-shaped support 12 (the diameter of which is substantially equal to or slightly smaller than the inner diameter of the sleeve 13) is inserted into the sleeve from the top of the sleeve and supported by the protrusion 13a. The cathode matrix 11 impregnated with the electron-emitting material is then inserted into the sleeve 13 from the same direction (the direction of the support 120? Supported). Then, the upper end of the sleeve 13 is joined corresponding to the upper edge of the cathode matrix 11, forming a flange-type fixing portion 13b. This can prevent the cathode matrix 11 from falling off from the top end of the sleeve 13. In the insert cathode manufactured according to the manufacturing method of the present invention, the cathode matrix 11 and the support 12 are fixed to the sleeve due to their physical structure rather than welding, which is essentially preventable due to welding Changes in the characteristics of the cathode matrix caused by heating. In particular, since the protrusion 13a and the sleeve 13 have been formed in advance, the insertion fixing portion 13b is formed after the support 12 and the cathode matrix 11 are installed, so unlike the conventional method, the surrounding of the sleeve does not occur. Deformed. The sleeve 13 is not deformed, which is conducive to the stable fixation of the cathode matrix 11 on the sleeve 11. The use of a disk-shaped holder 12 without an electron-shielding outer layer to replace the conventional cup-shaped reservoir of the cathode is advantageous in manufacturing, and because the mass is reduced, the overall heat capacity is also reduced. The reduction in heat capacity will cause the cathode to quickly reach its operating temperature, resulting in faster image output. The circular upper edge of the cathode matrix 11 facilitates the sintering of the cathode matrix and the formation of the fixed portion 13b of the sleeve 13. In addition, the broad electron emission surface 11a of the cathode matrix 11 greatly increases the electron emission efficiency. Although the present invention is specifically illustrated and described by referring to the preferred specific examples of the present invention, those skilled in the art must understand that for the present invention -8- --------------- ----------- installed ------ tr ------ line ------ 1 (please read the notes on the back before filling this page) This paper Another general purpose HS home standard apple (CNS) A 4 specifications (both 210 X Μ7 public) 82.3. 40, 〇〇〇2〇9ϋυ Α6Β6 V. Description of invention () It is obvious that different changes in form and details are not The spirit and scope of the invention as defined in the scope of the additional patent application will be captured. (Please read the precautions on the back and then fill out this page) The 5th -9 printed by the Men ’s Workers ’Consumer Cooperative of the Central Bureau of Standards of the Ministry of Economic Affairs — This paper scale is applicable to the China National Floating Standard (CNS> A 4 specifications (210 X 297 W per cent) 82.3 . 40,000