200902239 九、發明說明： 【發明所屬之技術領域】 本發明係有關於-種安全扳手結構，詳而言之綱於—種於施力過度 時，柄部將產生慢速撓曲，藉此_示使用者喊保❿力效之設計。 【先前技術】 按，台灣為工業技術王國，從製造、加工到維修，無一不是技術先進、 製造精良’因此工業產品深受世界各畴愛，從汽車製造職子加工，都 為本國帶來豐饒的收益，而產業在進行諸多作業時最常使用的設備即為手 工具，雖然部份具高度技術與危險環境之作業已漸由機器所取代，但是基 本之加工與維修翻以衫具之_才能完成，因此麵業者無一不在研 發更«、更人性化錢製造成本更魏廉之打具簡，其巾扳手為使 用中甚為頻繁者。 扳手之設計為-池前端具有_可與固定件嵌卡之頭部，藉此於握柄 處施力產生扭㈣鷄稱㈣定倾人频内，因而峡件之螺紋部與 被鎖入物產生歸力使兩物彼此固定，然而制此麵力扳手時，除施= 扳手之扭力因人而斜’獨之賴所需叙扭力亦麵柯，但板手所 能承受之扭力或卡獄果有賴度，若鮮設料良或制者操作時失力 過猛之情況下，扳手有可駿额_件彼此魏岭絲險，因此有業 者設計出扳手之防脫裝置。 習用之扳手防脫裝置請參财華民國專利公告號第4 5 9 5 9工號， 『扳手扳動螺帽防脫裝置』，其係為-種扳手扳動螺帽防脫裝置，其包括有： 200902239 一扳手，其-端設有-e端，另-端則固設-把手；一棘動件係以可轉動 方式里設於扳手之匣端内，該棘動件之内周緣係由數個壁面構成，而於每 -壁面上皆凹設有-限止部，且該限止部係未完全貫穿於壁面而形成—擔 緣；其中，當固定件位於棘動件内之第一位置時，該固定件係對人壁面間， 而可穿出於棘動件，而當固定件位於棘動件内之第二位呈時，該固定件係 對人壁面之限止勒，且受舰止部緣之卡制而無法穿出於棘動件^ 可達到對固定件之止擋及防脫功能。 然而’此種扳特絲置料與峡件較鱗密套設峨止滑脫之危 險’但其⑽略扳手讀所能承受之她扭力值，且扳手上之各部元件亦 有其極限強度’尤其當操作-些需以較大扭力以始可牢固鎖設之作^時,、 若扳手内讀鱗因超過其職承受之極限扭力辦，麻祕生「急速 崩齒」之情形，使棘動件_關壞而失去崩定件卡固之力量，若此時 操作者正處於大力扳動扳手之狀況下時，則容易因卡固力瞬間消失而跌 倒，此騎較具危雜之作業現場甚至騎作料，若科以去重心跌 倒使頭部賴顧❹高處跌落，將造成無可_之賴，·錢手其頭部 p使可承又較大之扭力’但頸部或柄部之可承受極限扭力值卻小於頭部 時，此時若施予極大之扭力，雖扳手頭部不致發生滑脫，但板手有可能因 應力大量針於頸部或㈣之脑處，岐然發生«之情形，此自然也 容易使操作__心而跌倒，甚至斷裂之扳手_飛脫而砸傷附 近之人員’因此就整體而言，其可說相當的不具有實用性，仍有加以改良 之必要。 200902239 【發明内容】 本發明之主要目的躲於提供—種安全扳手輯，其可改善習用之板 手因施力過大時可能突然發生斷裂而造成危險等缺失。 為達成前述之發明目的，本發明係包括一頭部以及—柄部，其中： 該頭部係供鎖設固定件之用，且其與該柄部連接，藉此當頭部與固定 件套設時，制紗柄職力峨本财錄力，_使岐刺扭力之 旋轉方向鎖场㈣，關定件亦畴反作狀扭力至描，並於本體造 成剪力與扭矩； 該柄部係與頭雜設，其係具—第_桿身與—第二桿身，該第一桿身 係較第二桿身為粗；該柄部内係設置—第—空間與—第二空間，該第一空 間係位於第—桿身内，而該第二空間係與第_空間連接並相通，且其係由 與第-空間連接處延伸至第二桿身内；該第—桿身之長度係定義為l工， 第二桿身之長度係定義為L2，該第-空間之長度係定義為L，第二空間 之長度係定義為L 3 ’且第-空間之内徑係定義為φΑ，第二空間之内徑 係定義為ΦΒ，而各定義之關係為[1>l、L2>l3以及㈣>_ ; 該柄部末_向储-螺減，該敝孔祕—賴件鎖設，藉此以防止 異物掉入柄部之第一空間内； 本體於使用時’使用者將頭部與固定件鎖設處做為支點，並於柄部之 第才于身處施力而產生扭力至固定件，此時固定件亦回傳反作用之扭力至 本體因而本體&反伽之扭力影響祕柄部產生扭域剪力，扭矩並於 ，但 柄P斷面上產生應力’且第二桿身為傳遞施力與承受反作用之扭矩處 200902239 由於第一桿身内之第一空間與第二空間連通，且第二空間並延伸至第二桿 身内，因此使第二桿身具有實心段與非實心段，非實心段因其斷面積較小 而使所受之應力值較實心段為高，因此第二桿身若能承受之應力值快達極 限時’非實心段因應力較高之原因而將預先產生慢速扭曲，並因此具警示 使用者之功效’據此以提醒本體將達臨界破壞之情況，並避免本體破壞時， 使用者尚在施力而失去重心跌倒，因此本發明可說是一種相當具有實用性 及進步性之發明，相當值得產業界來推廣，並公諸於社會大眾。 【實施方式】 本發明係有關於一種安全扳手結構，請參閱第一圖至第二圖所示，這 種安全扳手結構其本體（1)係包括一頭部（2 )以及一柄部（3 )，其中： 該頭部（2)係供鎖設固定件（4)之用，且其與該柄部（3)連接， 藉此當頭部（2 )與ϋ定件（4 )鎖設時，個者於柄部（3 )相對頭部 (2)之一端施力’而使本體（丄）以頭部（2)為支點產生扭力，因而 使固定件（4)順扭力之旋轉方向鎖入物體内，而此時固定件亦回 傳反作用之扭力至本體⑴，並於本體⑴造成剪力與扭矩； 該柄部（3)係與頭部（2)組設，且柄部（3)係具-第-桿身（3 1)與—第二桿身（3 2 )，該第-桿身（3 1)係較第二桿身（3 2 )為 粗’第—桿身（31)與第二桿身（3 2)連接處係往第二桿身（3 2) 方向漸縮而呈較粗至較細之狀態，而頭部（2)與第二桿身（3 2)連接 處係往第—桿身（3 2)方向漸縮而呈較粗至較細之狀態；又該柄部（3) 内係设置一第一空間（3 3)與一第二空間（3 4)，該第一空間（3 3) 200902239 係位於第一桿身（3 i) 連接並相通，且其係由鱼第空間（34)係與第一空間（33) 内；該第-桿身（川3)連接處延伸至第二桿身（3 2) 传1幻9 1 )之長度做義為L1，第二《(3 2)之長度 係疋義為L2，#亥第一空問「〇 0、 (3 3)之長度係定義為[，第二空間（3 4) 之長度係定義為L 3，且坌—/ 二閒（3 3)之内徑係定義為①八，第二空 間（34)之内徑係定義為㈣，而各定義之關係為li>l、l2>l 3以及ΦΑ>Φβ ;該㈣（3 )她嫩-佩（3 5 )，該螺 5 )係么、封閉件（3 5 1 )鎖設，藉此以防止異物掉入柄部（3 ) 之第一空間（3 3)内； 由於第一桿身（31)係為主要受握持施力處，而以頭部（2)與固 疋件（4)鎖設處為支點，因而你望 | u而攸弟一柃身（31)至頭部（2)為力臂 而產生扭力’且1U件（4 )錄力影響而亦回傳反制之扭力至頭部 (2 )，並於本體⑴產生扭矩與剪力，而藉由本體⑴之強度以抵 抗扭矩及剪力以避免本體⑴斷裂或彎曲；但從第—桿身（3丨）可知 其為主要受握持施力處，而第二桿身（3 2)係傳遞第—桿身（3丄）之 施力，以及受頭部（2)回傳反作用之扭矩處，因此第二桿身（3 2)係 為本體（1)中农谷易發生扭矩或剪力過大而彎曲或斷裂處，若反覆施力 而使第二桿身（3 2)常處於超過降伏強度之情況下，其材料性質容易脆 弱而破壞，但由於本體（1)内與第一空間（3 3)連接之第二空間（3 4)係延伸入第二桿身（3 2)内，因此使第二桿身（3 2 )具有一實心 段（3 2 1)以及一非實心段（3 2 2)，該實心段（3 21)與非實心 200902239 段（3 2 2 )係可傳遞施力以及承受反作用之扭矩，但非實心段（3 2 2) 因呈中空而使剪力及扭矩傳遞時集中於其非中空處，而使其斷面上因扭矩 產生之應力較實心段（3 21)為向，而以相同材質之實心段（3 21) 與非實心段（3 2 2 )而言，由於非實心段（3 2 2)斷面之應力較實心 丰又（321)為南，因此若第二桿身（3 2)處之實心段（3 2 1)所能 承受之應力值快達極限時，非實心段（3 2 2 )將預絲應力過高而產生 慢速扭曲，藉此以警告使用者本體（i)已將達臨界破壞之情況，而避免 本體（1)破壞時失去重心而跌倒；又該柄部（3 )因具有第一與第二空 間（3 4 )而使其呈非實心之態樣，因此可使本體⑴輕質化，使用者 操作時更感覺輕便而不易因過重而使肌肉酸痛。 本體（1)於使用時’請參閱第三圖至第四圖所示，使用者將頭部（2) 與固定件（4)鎖設處做為支點，並於柄部（3)之第—桿身（3）處 施力而產生扭力至ϋ定件（4)，此_餅（4)亦轉反侧之扭^ 至本體（1 )，因而树⑴受反制之扭力影響而於柄部⑶產生 扭矩與剪力，扭矩並於柄部（3)斷面上產生應力，而柄部（3)斷面上 之應力值_面面積而麵不同，且第二桿身（3 2 )為傳遞施力與承受 反作用之扭矩處，但由於第-桿身（31)内之第-空間（3 3)與第二 空間（3 4)連通，且第二空間（3 4)並延伸至第二桿身（3 2)内， 因此使第二桿身（3 2 )具有實‘。段（3 2 1)與非實吨（3 2 2 ) 非實心段（3 2 2 )因其封空處所受之應力值較實心段（3 2 i )為高， 因此第一；^身（3 2 )若能承受之應力值快達極限時，非實心段（3 2 2 ) 200902239 •因應力較高之原因而將預先產生慢速扭曲，係如第四圖所示，第二桿身（3 .2 )發生扭曲而具警示使用者之功效，據此以提醒本體⑴將達臨界破 壞之情況，並避免本體⑴破壞時，個者尚在施力而失去重心跌倒。 本發明係利用柄部（3)内具第—空間（3 3)與第二空間（3 4) 而呈非實心之狀態，其除可減輕本體（工）之重量外，並由於第二空間（3 4)係延伸至第二桿身（3 2)内，而使第二桿3 2)具有實心段（3 f 非實^又（3 2 2)，且非實心段（3 2 2)之斷面因扭矩所產 生之應力值較實心段（3 2 i )為高，因此本體⑴欲破壞時，將於第 二桿身（3 2 )之非實心段（3 2 2 )預先產生慢速減，藉此以警告使 用者而避就險之發生，因此本伽可說是相#具賴制者安全之發明。 由上所述者僅為肋解釋本發明之較佳實關，麟企_以對本發 月做任何形式上之限制’是以，凡有在相同之發明精神下所做有關本發明 之任何修飾或變更者’皆仍聽括在本發明意圖保護之範嘴内。 综上所述，本發明安全扳手結構在結構設計、使用實用性及成本效益 上，確實是完全符合產業上發展所需，且所揭露之結構發明亦是具有前所 未有的創新構造，所以其具有「新穎性」應無疑慮，又本發明較之習知結 構更具功效之增進，因此亦具有「進步性」，其完全符合我國專利法有關發 明專利之申請要件的規定’乃依法提起專利申請，並敬請柄早日審查， 並給予肯定。 11 200902239 【圖式簡單說明】 第一圖係本發明安全扳手結構剖面示意圖。 第二圖係本發明安全扳手結構立體剖視示意圖。 第三圖係本發明安全扳手結構使用示意圖。 第四圖係本發明安全扳手結構使用示意圖。 【主要元件符號說明】 1- 一本體 2 — —頭部 3 — 柄部 3 1- 一第一桿身 3 2- 一第二桿身 3 2 1- 一實心段 3 2 2- 一非實心段 3 3 — 一第一空間 3 4 — 一第二空間 3 5- 一螺紋孔 3 5 1 — 一封閉件 4- 一固定件 12200902239 IX. Description of the Invention: [Technical Field] The present invention relates to a safety wrench structure, and in detail, when the force is excessive, the handle will produce a slow deflection, thereby Show the user shouting the design of the protective effect. [Prior Art] According to Taiwan, Taiwan is an industrial technology kingdom. From manufacturing, processing to maintenance, all of them are technologically advanced and well-made. Therefore, industrial products are deeply loved by the world, and they are brought from the automobile manufacturing industry. Abundant benefits, and the most commonly used equipment in the industry for many operations is hand tools. Although some of the highly technical and hazardous environments have been replaced by machines, the basic processing and maintenance is turned into a shirt. _ can be completed, so the face of the industry is no longer in the development of more «, more humanized money manufacturing costs more Wei Lian's simple brush, its towel wrench is very frequent in use. The design of the wrench is that the front end of the pool has a head that can be engaged with the fixing member, thereby applying a force to the handle at the grip to generate a twist (four) chicken scale (four) fixed tilting frequency, and thus the threaded portion of the isthmus and the locked object The force is generated to fix the two objects to each other. However, when the force wrench is used, except for the torque of the wrench, the torque of the wrench is inclined by the person, and the required torque is also the same, but the wrench can withstand the torque or the jail. If there is a good degree of material, if the fresh material is good or the system is too weak when operating, the wrench can have a balance of _ pieces of Wei Ling, so some operators have designed the anti-off device of the wrench. For the use of the wrench's anti-off device, please refer to the No. 4 5 9 5 9 work number of the Republic of China, the "wrench nut pull-off device", which is a wrench-type nut anti-off device, which includes There are: 200902239 A wrench with a -e end at the end and a - handle at the other end; a ratchet member is rotatably disposed in the end of the wrench, the inner periphery of the ratchet The utility model is composed of a plurality of wall surfaces, and each of the wall surfaces is concavely provided with a limiting portion, and the limiting portion is not completely penetrated through the wall surface to form a burring; wherein, when the fixing member is located at the first position in the swaying member When the fixing member is paired between the wall faces of the person, the piercing member can be worn, and when the fixing member is located in the second position in the ratchet member, the fixing member is limited to the wall of the human body and is supported by the ship. The locking of the retaining edge can not be worn by the ratcheting member ^ to achieve the stop and anti-off function of the fixing member. However, 'the kind of the wire and the girdle are more sturdy and the risk of slipping off the slippery', but the (10) can read the torque value that the wrench can withstand, and the components on the wrench also have the ultimate strength. Especially when the operation needs to be locked with a large torque, it can be firmly locked. If the reading scale in the wrench exceeds the limit torque of the position, the hemp will be "quickly disintegrating". If the operator is in a situation where the operator is vigorously pulling the wrench, it is easy to fall due to the momentary disappearance of the card force. This ride is more dangerous. Even if the scene is even riding, if the branch falls to the center of gravity and falls down on the head, it will cause no blame, and the head of the hand can make a large torque. But the neck or handle If the torque of the part can withstand the limit torque is less than the head, if the torque is applied to the head, the wrench head will not slip, but the wrench may have a large amount of needles on the neck or (4) brain due to stress. However, the situation of «this is naturally easy to make the operation __ heart fall, even the wrench of the break _ fly The injured persons near the 'So on the whole, it may not be quite practical, there is still the need to be improved. 200902239 SUMMARY OF THE INVENTION The main object of the present invention is to provide a safety wrench that can improve the risk of a sudden danger due to sudden breakage of a conventional wrench. To achieve the foregoing objects, the present invention includes a head and a handle, wherein: the head is for locking a fixing member, and is coupled to the handle, thereby arranging the head and the fixing member At the time, the shank of the yarn handles the power of the treasury, _ so that the direction of rotation of the spurs of the twisting force locks the field (four), the closing parts are also reversed to the torque, and the shearing force and torque are generated on the body; And the head miscellaneous, the tie--the shaft and the second shaft, the first shaft is thicker than the second shaft; the handle is provided with a first space and a second space, The first space is located in the first shaft, and the second space is connected and communicated with the first space, and is extended from the connection with the first space to the second shaft; the length of the first shaft is defined For the work, the length of the second shaft is defined as L2, the length of the first space is defined as L, the length of the second space is defined as L 3 ' and the inner diameter of the first space is defined as φ Α, The inner diameter of the two spaces is defined as ΦΒ, and the relationship between the definitions is [1>l, L2>l3 and (4)>_; Subtracting, the boring secret-locking device is used to prevent foreign matter from falling into the first space of the handle; when the body is in use, the user uses the head and the fixing member as a fulcrum, and The first part of the department produces a torque to the fixed part when the force is applied. At this time, the fixed part also returns the reaction torque to the body, so the body & However, the stress is generated on the shank P section and the second shaft is the torque transmitting the force and the reaction. The second space is connected to the second space, and the second space extends to the second pole. In the body, therefore, the second shaft has a solid section and a non-solid section, and the non-solid section has a higher stress value than the solid section due to the smaller sectional area, so the second shaft can withstand the stress value quickly. When the limit is reached, the non-solid segment will be pre-generated with slow distortion due to high stress, and thus alert the user to the effect of the user's critical damage and avoid the destruction of the body. Still exerting force and losing focus Therefore, the present invention can be said to be a quite practical and progressive invention, which is quite worthy of promotion by the industry and is publicized to the public. [Embodiment] The present invention relates to a safety wrench structure. Referring to the first to second figures, the safety wrench structure has a body (1) including a head (2) and a handle (3). ), wherein: the head (2) is for locking the fixing member (4), and is connected to the handle (3), thereby when the head (2) and the fixing member (4) are locked The individual applies a force to one end of the handle (3) relative to the head (2) to cause the body (丄) to generate a torsion force with the head (2) as a fulcrum, thereby locking the fixing member (4) in the direction of rotation of the torque Inside the object, the fixing member also returns the reaction torque to the body (1), and causes shearing force and torque on the body (1); the handle (3) is assembled with the head (2), and the handle (3) a pair of - a shaft (3 1) and a second shaft (3 2), the first shaft (3 1) being a thicker 'first shaft than the second shaft (3 2) 31) The joint with the second shaft (32) is tapered toward the second shaft (3 2) to be thicker to thinner, while the head (2) and the second shaft (3 2) The joint is tapered toward the first shaft (3 2) and is thicker than a fine state; a handle (3) is provided with a first space (3 3) and a second space (3 4), the first space (3 3) 200902239 is located at the first shaft (3 i Connected and connected, and it is connected by the fish space (34) and the first space (33); the joint of the first shaft (Chuan 3) extends to the second shaft (3 2) 1) The length is defined as L1, and the length of the second "(3 2) is L2, #亥一空问"〇0, (3 3) is defined as [, second space (3 4) The length is defined as L 3 , and the inner diameter of 坌-/二闲(3 3) is defined as 1 eight, the inner diameter of the second space (34) is defined as (4), and the relationship between definitions is li> ;l, l2>l 3 and ΦΑ>Φβ; (4)(3) her tender-peel (3 5), the screw 5), the closure (3 5 1) is locked, thereby preventing foreign matter from falling in The first space (3 3) of the handle (3); because the first shaft (31) is mainly held by the holding force, and the head (2) and the fixed part (4) are locked As a fulcrum, you look at it | u and the younger brother (31) to the head (2) to generate torque for the arm and '1U (4) recorded The force influence also returns the counter-torque to the head (2), and produces torque and shear on the body (1), while the strength of the body (1) resists torque and shear to avoid the body (1) breaking or bending; The first shaft (3丨) is known to be mainly the holding force, while the second shaft (32) transmits the force of the first shaft (3丄) and is subjected to the head (2). Passing the reaction torque, so the second shaft (3 2) is the body (1), the agricultural valley is prone to torque or shearing force is too large to bend or break, if the force is applied repeatedly to make the second shaft (3 2) Often in the case of exceeding the strength of the fall, the material properties are easily fragile and destroyed, but the second space (34) connected to the first space (3 3) in the body (1) extends into the second shaft (3) 2), so that the second shaft (32) has a solid section (3 2 1) and a non-solid section (3 2 2), the solid section (3 21) and the non-solid 200902239 section (3 2 2 ) is a torque that can transmit force and withstand reaction, but the non-solid section (3 2 2) is hollow, so that the shear force and torque are transmitted in the non-hollow area, so that The stress due to the torque on the section is closer to the solid section (3 21), and the solid section (3 21) and the non-solid section (3 2 2 ) of the same material are due to the non-solid section (3 2 2 The stress of the section is more solid than that of the solid (321), so if the stress value of the solid section (3 2 1) at the second shaft (32) can reach the limit, the non-solid section (3) 2 2) The pre-wire stress is too high to produce a slow twist, thereby warning the user that the body (i) has reached critical damage, and avoiding the body (1) losing the center of gravity and falling; (3) Since the first and second spaces (3 4 ) are in a non-solid state, the body (1) can be made lighter, and the user feels lighter when operating, and is less likely to be sore because of excessive weight. When the body (1) is in use, please refer to the third to fourth figures. The user uses the head (2) and the fixing member (4) as the fulcrum and the shank (3). - the shaft (3) exerts a force to generate a torsion force (4), and the cake (4) also turns to the opposite side to the body (1), so that the tree (1) is affected by the counter-torque force and is applied to the handle The part (3) generates torque and shear force, and the torque generates stress on the cross section of the shank (3), and the stress value on the cross section of the shank (3) is different from the surface area, and the second shaft (3 2 ) To transmit the force applied and react to the torque, but because the first space (3 3) in the first shaft (31) is in communication with the second space (34), and the second space (34) extends to Within the second shaft (32), thus the second shaft (32) has a real '. The segment (3 2 1) and the non-solid tonnage (3 2 2 ) non-solid segment (3 2 2 ) are higher in stress than the solid segment (3 2 i ) because of the height of the space, so the first; 3 2) If the stress value that can withstand the limit reaches the limit, the non-solid section (3 2 2 ) 200902239 • The slow distortion is pre-generated due to the higher stress, as shown in the fourth figure, the second shaft (3. 2) Distortion and warning of the user's effect, according to this reminds the body (1) will reach the critical destruction situation, and avoid the body (1) destruction, the individual is still exerting force and loses the center of gravity. The invention utilizes the first space (3 3) and the second space (3 4) in the handle (3) to be in a non-solid state, which can reduce the weight of the body (work), and the second space (3 4) extends into the second shaft (32), and the second rod 3 2) has a solid segment (3f is not real ^3 (2 2 2), and the non-solid segment (3 2 2) The stress value of the section due to the torque is higher than the solid section (3 2 i ), so when the body (1) is to be destroyed, the non-solid section (3 2 2 ) of the second shaft (3 2 ) is pre-generated slowly. The speed reduction, in order to warn the user and avoid the danger, so this gamma can be said to be the invention of the safety of the system. The above is only a rib to explain the better practice of the invention, Lin The company _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ In summary, the structure of the safety wrench of the present invention is completely in line with the development of the industry in terms of structural design, practicality and cost-effectiveness, and the disclosed knot The invention also has an unprecedented innovative structure, so its "novelty" should be undoubtedly considered, and the invention is more effective than the conventional structure, and therefore has "progressiveness", which fully complies with the invention of the patent law of China. The provisions of the patent application requirements are patented in accordance with the law, and are subject to early review and affirmation. 11 200902239 [Simple description of the drawings] The first figure is a schematic cross-sectional view of the safety wrench structure of the present invention. Schematic diagram of the structure of the safety wrench. The third figure is a schematic diagram of the structure of the safety wrench of the present invention. The fourth figure is a schematic diagram of the structure of the safety wrench of the present invention. [Description of main components] 1- a body 2 - head 3 - handle Part 3 1- a first shaft 3 2- a second shaft 3 2 1- a solid segment 3 2 2- a non-solid segment 3 3 - a first space 3 4 - a second space 3 5- Threaded hole 3 5 1 — a closure 4 - a fixture 12