— 0 —任務(wù)書(理工類)學(xué)生姓名： 專 業(yè)： 班 級： 學(xué) 號： 指導(dǎo)教師： 職 稱： 完成時間： 畢業(yè)設(shè)計(論文)題目： 汽車起重機舉升機構(gòu)的設(shè)計縱向課題（ ） 理論研究（ ）教師科研課 題 橫向課題（ ） 應(yīng)用研究（ ）教師自擬課題（√） 應(yīng)用設(shè)計（√）題目來源學(xué)生自擬課題（ ）題目類型其 他（ ）注：請直接在所屬項目括號內(nèi)打“√”總體設(shè)計要求及技術(shù)要點：汽車起重機是裝在普通汽車底盤或特制汽車底盤上的一種起重機，其行駛駕駛室與起重操縱室分開設(shè)置。論文首先針對國內(nèi)外發(fā)展現(xiàn)狀及設(shè)計內(nèi)容作出相關(guān)概述。其次，按照起重機舉升機構(gòu)的設(shè)計過程，完成對機構(gòu)的選型、機構(gòu)的受力分析和計算、液壓系統(tǒng)的設(shè)計。 工作環(huán)境及技術(shù)條件：對汽車起重機舉升機構(gòu)進(jìn)行結(jié)構(gòu)設(shè)計、液壓系統(tǒng)設(shè)計。工作內(nèi)容及最終成果：1、介紹國內(nèi)外汽車起重機的發(fā)展概況；2、汽車起重機舉升機構(gòu)的進(jìn)行結(jié)構(gòu)設(shè)計；3、對舉升機構(gòu)的液壓系統(tǒng)進(jìn)行設(shè)計；4、最終成果為汽車起重機舉升機構(gòu)的設(shè)計報告?！?1 —時間進(jìn)度安排：廣泛查閱參考資料，重點閱讀重要參考文獻(xiàn)；汽車起重機舉升機構(gòu)的結(jié)構(gòu)設(shè)計；舉升機構(gòu)的液壓系統(tǒng)進(jìn)行設(shè)計；撰寫論文，準(zhǔn)備答辯。指導(dǎo)教師簽字： 年 月 日教研室主任意見：教研室主任簽字： 年 月 日共 15 頁 第 1 頁外 文 翻 譯共 15 頁 第 2 頁譯文標(biāo)題 起重機的發(fā)展與介紹原文標(biāo)題 Crane development and Introduction作 者 Elkeson 譯 名 埃爾克森 國 籍 美國原文出處譯文：發(fā)展隨著現(xiàn)代科學(xué)技術(shù)的迅速發(fā)展，工業(yè)生產(chǎn)規(guī)模的擴大和自動化程度的提高，起重機在現(xiàn)代化生產(chǎn)過程中應(yīng)用越來越廣，作用愈來愈大，對起重機的要求也越來越高。尤其是計算機技術(shù)的廣泛應(yīng)用，許多跨學(xué)科的先進(jìn)設(shè)計方法出現(xiàn)，這些都促使起重機的技術(shù)進(jìn)入嶄新的發(fā)展階段。起重機發(fā)展趨勢,輕型化和多樣化。有相當(dāng)批量的起重機是在通用的場合使用，工作并不很繁重。這類起重機批量大、用途廣，考慮綜合效益，要求起重機盡量降低外形高度，簡化結(jié)構(gòu)，減小自重和輪壓，也可使整個建筑物高度下降，建筑結(jié)構(gòu)輕型化，降低造價。因此電動葫蘆橋式起重機和梁式起重機會有更快的發(fā)展，并將大部分取代中小噸位的一般用途橋式起重機。德國德馬格公司經(jīng)過幾十年的開發(fā)和創(chuàng)新，已形成了一個輕型組合式的標(biāo)準(zhǔn)起重機系列。起重量為 1-63 噸，工作級別為 A1-A7，整個系列由工字形和箱型單梁、懸掛箱形單梁、角形小車箱形單梁和箱形雙梁等多個品種組成。主梁與端梁相接以及起重小車的布置有多種型式，可適合不同建筑物及不同起吊高度的要求。根據(jù)用戶需要每種規(guī)格起重機都有三種單速及三種雙速供任意選擇，還可以選用變頻調(diào)速。操縱方式有地面手電門自行移動、手電門隨小車移動、手電門固定、無線遙控、司機室固定、司機室隨小車移動、司機室自行移動等七種選擇。大車及小車的供電有電纜小車導(dǎo)電、DVS 系統(tǒng)兩種方式。如此多的選擇項，通過不同的組合，可搭配成百上千種起重機，充分滿足用戶不同的需求。這種起重機的另一最大優(yōu)點是輕型化，自重輕、輪壓輕、外形尺寸高度小，可大大降低廠房建筑物的建造成本，同時也可減小起重機的運行功率和運行成本。與通用產(chǎn)品相比較，起重量為 10t，跨度 22.5m，通用雙梁橋式起重機自重是 24t，起重機軌面以上高度 1876mm，起重機寬度 5980mm； 德馬格起重機的自重只有 8.7t，重量輕了 176%，起重機軌面以上高度為 920mm，降低了 104%，起重機寬度為2980mm，外形尺寸減少了 100%。自動化和智能化,起重機的更新和發(fā)展，在很大程度上取決于電氣傳動與控制的改進(jìn),實現(xiàn)起重機的自動化和智能化。大型高效起重機的新一代電氣控制裝置已發(fā)展為全電子數(shù)字化控制系統(tǒng)。主要由全數(shù)字化控制驅(qū)動裝置、可編程序控制器、故障診斷及數(shù)據(jù)管理系統(tǒng)、數(shù)字化操縱給定檢測等設(shè)備組成。變壓變頻調(diào)速、射頻數(shù)據(jù)通訊、故障自診監(jiān)控、吊具防搖的模糊控制、激光查找起吊物重心、近場感應(yīng)防碰撞技術(shù)、現(xiàn)場總線、載波通訊及控制、無接觸供電及三維條形碼技術(shù)等將廣泛得到應(yīng)用。使起重機具有更高的柔性，以適合多批次少批量的柔性生產(chǎn)模式，提高單機綜合自動化水平。重點開發(fā)以微處理機為核心的高性能電氣傳動裝置，使起重機具有優(yōu)良的調(diào)速和靜動特性，可進(jìn)行操作的自動控制、自動顯示與記錄，起重機運行的自動保護與自動檢測，特殊場合的遠(yuǎn)距離遙控等，以適應(yīng)自動化生產(chǎn)的需要。介紹共 15 頁 第 3 頁在修橋筑路等建設(shè)中，常常有大量的物料、零部件、成品需要運輸，大量的物料搬運在建筑工地、采石廠、鐵路、港口和倉庫中都存在。水泥廠、灰泥廠和長期加強混泥產(chǎn)品都需要各種物料提升機械。在倉庫等場所所做維修工作，也將用到起重機械可作間歇作業(yè)或連續(xù)作業(yè)。根據(jù)機械作用目的不同，可分為以下主要兩類：a 起重機械 如：絞車、千斤頂、升降機和連續(xù)起重機；b 運輸機械：各種運輸設(shè)備（傳送帶、吊桶、螺旋機、纜索、氣后操縱設(shè)備）和裝載設(shè)備（叉車、單斗車）。1. 起重機主要參數(shù)（1） 提升能力：特定條件下起重機最大吊起量。（2） 提升高度：從地面把貨物提升到最大位置時吊鉤中心的最低點的垂直距離。（3） 幅度：起重機旋轉(zhuǎn)軸線到取物裝置中心線之間的距離。（4） 跨度：起重機運行軌道軸線之間的水平距離。（5） 工作速度：起重各機構(gòu)（提升、運行、下降、旋轉(zhuǎn)）的速度。（6） 空間尺寸和重量（7） 穩(wěn)定性：固定起重機的錨釘、壓板或其它裝置應(yīng)保證起重機在工作情況下，起重臂各個方向的穩(wěn)定保證，在暴風(fēng)雨等惡劣條件下起重機穩(wěn)定。如果是有軌起重機，固定裝置在計算起重機穩(wěn)定性時不應(yīng)計算在內(nèi)。2. 起重機的重要零件吊鉤吊鉤用來提取重物，可分為單鉤和多鉤或板鉤。盡管通常的做法是將吊鉤懸掛在（滑輪組）殼體內(nèi)的滑輪上，當(dāng)裝卸小負(fù)荷（重小于 3 噸）時，吊鉤可直接裝在鋼絲繩方向自由運動。當(dāng)貨物達(dá)到 40 噸時應(yīng)采用抗剪鉚接吊鉤 B.S3017 或三角型 B.S3317 吊鉤，還需裝置鎖定機構(gòu)，防止吊鉤旋轉(zhuǎn)。鋼絲繩鋼絲繩是由可彎曲的能傳遞力的重要零件。鋼絲繩由直徑 0.5mm-2mm 的鋼絲纏繞而成，可承受 1400-2000 的拉力，鋼絲繩有不同的形式，建筑或道2mN路建設(shè)中經(jīng)常采用直徑為 1mm-32mm 的各種材料雙向繞（正向和反向）鋼絲繩。雙繞鋼絲繩是用預(yù)先繞成螺旋狀的鋼絲般制造的，鋼絲的纏繞方式和鋼絲繩的纏繞方式是一樣的，正向繞制的鋼絲繩中的雙繞鋼絲是反向絞繞的。為使鋼絲繩有足夠的可繞性和潤滑性，可采用浸泡在潤滑油的纖維繩芯。在起重領(lǐng)域還可碰到一種特殊的編織而成的鋼絲繩。這種繩一般用于觸輪設(shè)備，它的表面形成特殊的潤滑層，這種繩可繞性低，但防潮耐用?；喓途硗不喌淖饔檬菍?dǎo)向和支承鋼絲繩?；喩系牟鄣倪吘壱幸?guī)定的形狀以免夾住鋼絲繩?；喌拿x直徑為滑輪槽底直徑 D，滑輪直徑的大小直接影響鋼絲繩的彎曲力的大小和鋼絲繩的壽命，用此滑輪直徑的選擇一定要按照標(biāo)準(zhǔn)。在提升或拖拉貨物時，鋼絲繩會在光滑的有槽的卷筒表面受到損害。還使單根繩子上的壓力較小，這樣可以延長鋼絲繩的壽命。制動器制動裝置是起重機提升重物過程的一個重要裝置電力起重機裝有一個自動的電控制動器，當(dāng)貨物突然失控時它將由交流螺旋線圈起動，為防止重物下降時失速，有時裝上一個離心式制動器，但采用電位計動態(tài)控制的電制動器能使重物放共 15 頁 第 4 頁慢速度達(dá)到正確移動效果，產(chǎn)生的力矩可使功力裝置對其靈活的控制。在沃特連納德系統(tǒng)中經(jīng)常會用到一個大型動力裝置，它可以單一控制的傳動裝置高速，它的動力發(fā)生器可節(jié)約通用控制器的花費，制動器由高強度金屬制成，有光滑的摩擦表面、無裂紋.共 15 頁 第 5 頁原文：DevelopmentWith fast developments of the modern technology, the expansion of industrial production and the growth of the automatic level, applications of the carne in the modern manufacture have been more and more extensive, the effect has been bigger and bigger. Higher and higher requirement has been caused. Especially, with the broad application of computer technology and the appearance of the advanced design method of a lot of inter discipline, which urge the technology of the carne into a brand-new seed time. Hoist crane development tendency, light and diversification. Has the suitable batch the hoist crane is in the general situation use, the work not very is certainly arduous. This kind of hoist crane batch big, the use is broad, considered the synthesis benefit, requests the hoist crane to reduce the contour altitude as far as possible, the simplification structure, reduces is self-possessed with the wheel- pressure, also may cause the entire building highly to drop, construction structure light, reduces the construction cost. The electric hoist bridge type hoist crane and the beam crane can have a quicker development, and majority of substitutions in small tonnage general-utility bridge type hoist crane. The German Germany Maagcomp any passes through several dozens years development and the innovation, has formed a light combined type standard hoist crane series. The lifting capacity is 1-63 ton, the work rank is A1-A7, the entire series by labor character shape and box Shan Liang, is hanging box shape Shan Liang, angular small carriage shape Shan Liang Hexiang shape double Liang and so on many varieties is composed. The king post and the end girder docking as well as the crab arrangement has the many kinds of patterns, may suit the different building and the different hoisting up high request. Needs each kind of specification hoist crane according to the user all to have three kind of Shan Su and three kinds double fast for will fully chooses, but also may select the frequency conversion velocity modulation. The operation way has the ground electric switch voluntarily to move, the hand electric switch moves, the hand electric switch fixedly along with the car, the wireless remote control, control room is fixed, control room moves along with the car, control room voluntarily moves and so on seven kind of choices. The large cart and the car power supply has the electric cable car electric conduction, the DVS system two ways. The so many choices item, through the different combination, may match hundred and thousand of kind of hoist cranes, fully meets the user different need. This kind of hoist crane another biggest merit is light, is self-possessed lightly, the wheel-pressure light, the external dimensions is highly small, may greatly reduce the workshop building the construction cost, simultaneously also may reduce the hoist crane the working power and the movement cost. Compares with the general product, the lifting capacity is 10t, span 22.5m, the general double beam bridge type hoist crane dead weight is 24t, hoist crane track surface above highly 1876mm, hoist crane width 5980mm; The German hoist crane dead weight only had 8.7t, the weight has been light 176%, the hoist crane track surface above highly was 920mm, reduced 104%, the hoist crane width is 2980mm, the external dimensions reduced 100%. The automation and the intellectualization, the hoist crane renew land the development, is decided in the very great degree by the electrical transmission and the control improvement, realizes the hoist crane .Automation and the intellectualization. The large-scale highly effective hoist crane new generation of electricity control device has developed for the entire electron numerical control system . Mainly by entire numerical control drive, the programmable fore word controller, the breakdown diagnosis and the data management system the digitized operation assigns equipment and so on examination is composed. The live pressure frequency conversion velocity modulation, the radio frequency data communication, the breakdown from will examine the fuzzy control, the laser search hoisting up center of gravity, the near field induction which the monitoring, the hoist will guard against 共 15 頁 第 6 頁swings guards against the collision technology, the field bus, the carrier-current communication and the control, the non- contact power supply and the three dimensional barcode technology and so on widely obtains the application. Enable the hoist crane to have a higher flexibility, suits many raids of few batches the flexible production pattern, raises the single plane synthesis automation level. The key development take the microprocessor as the core high performance electricity transmission device, enable the hoist crane to have the fine velocity action and the static dynamic characteristic, may carry on the operation the automatic control, the automatic demonstration and the record, the hoist crane movement automatic protection and the automatic detection, the special occasion long-distance range remote control and so on, meets the automated production needIntroductionVast quantities of materials,parts and products have to be moved in road and bridge construction.Loads are handled in construction and erection jobs, in loading materials excavated from quarries or delivered by railway and water transport onto trucks and other vehicles,and in storehouses servicing the construction site.Factories producing concrete,mortars and prefabricated reinforced-concrete products widely utilize all kinds of materials bandling equipment,as do various depots.All materials hangdling equipment is either intermittent or continuous-action.Depending on its purpose,it consists of the following two main groups:a、Hoisting machinery:winches,jacks,hoists and cranks for intermittent operation.b、Conveyingmachinery:conveyors(belt,bucket,screw,cableways,air-operated equipment)and loading equipment (fork-life,single-bucket loader).1.Main Parameters of Cranes（1）Lifting Capacity:The maximum load under specified condition for which the crane may be used.（2）Height of Lift:The vertical distance between the ground level or datum level,and the lowest point of the throat of the hook when the hook is in the highest working position.（3）Radius:The horizontal distance measured between the centerline of the hook and a perpendicular projected through the center of rotation.（4）Track center:The horizontal distance between the centers of each pair of track rails.（5）Working speeds:The working speeds of different mechanisms(hoisting,traveling,derricking slewing)for crane.（6）Overall Dimensions and Weight.（7）Stability:The anchoring and/or ballasting of the crane shall be such as to ensure that with the jib in any position the righting moment imposed under service conditions.Under storm conditions the crane shall be stable.If the crane is rail mounted,the devices for anchoring the crane to the rails shall not be taken into account when determining the stability of the crane.2.Specific Parts for CranesHooksThey are used to lift loads,There are single hooks and solid or built-up dual hooks.To handling small loads(upto 3 tons)a hook may be attached directly to the free end of the rope,although the usual practice is to suspend the hook in a casing with a moving rope sheave.A bearing seating ring supporing the hook nut allows the load and the hook to turn freely around the vertical axis.For loads exceeding 40 tons,hooks of the ramshorn type,B.S3017,or of the triangular type,B.S3317,are preferable.If required,a locking device shall be fitted to prevent rotation of the hook.Steel wire Ropes共 15 頁 第 7 頁Steel wire ropes are used as flexible appliances to lift loads and transmit motion and forces.such ropes are wound from steel wire from 0.5 mm to 2 mm in diameter and have an ultimate strength of 1400-2000 .Steel wire ropes are available in a great variety of 2mNdesigns. Machines used in amterials handling, construction and road making are provided mostly with round double lay (cross or regular lay)ropes from 11 mm to 32 mm in dismeter.Double lay ropes are manufactured from preliminarily twisted spiral wire strands.In a parallel(Long)lay rope the direction of twist of the direction of twist of the wires in the strand is the same as that of the atrands in the rope,while regular lay ropes are so constructed that the direction of twist of the wires in the strand is opposite to that strands in the rope.To make the ropes more flexible and provde proper lubrication of wires of the strands are laid on a hemp core impregnated with oil.Special locked-coil steel wire ropes find application in cable cranes and cable ways.These ropes,used to carry trolleys,have the cross section.The outer specially shaped wires form a smooth surface.These ropes have a low flexibility and high resistance to wear and keep out moisture.Lleys and DrumsRopes are supported and guided by means of cast iron pulleys.The groove on the pulley rim is shaped so as not to pinch the rope.The nominal diameter of the pulley D is the diameter of the circle described by the exis of the rope.The pulley diameter appreciably affects the magnitude of the bending stresses and the rope servive life and for this reason the existing norms should be taken into account in selecting a pulley diameter.During lifting or other displacement of the load the rope may be wound around drums drums in the form of cylinders with a smooth or grooved surface.A rope resting in a groove ensures,besides the proper direction,a smaller pressure on separate wires in the rop which increase the rop service life.BrakesOne of the most important components crane is the brake on the hoisting motion.Electric cranes are invariably fitted with an automatic electric-mechanical brake actuated by solenoid or on alternating current by a thrustor which applies itself immediately current is cut off from the motor.Centrifugal brakes are occasionally fitted to prevent excessive acceleration when lowering,but it is preferable to use some system of electric braking such as dynamic with potentiometer control on direct current,and one of the systems of creating an opposing torque with alternating current.Slow speeds for accurate movement can be obtained by a manual brake applied to create a torque and so load up the motor to make it sensitive to resistance control.On large power installations the Word Leonard system is frequently used as it provides for a large range of speeds with simple control gear but the cost of the motor generator set offsets the saving in cost of main current controllers.Brake drums are preferably made of a high tensile iron which maintains a smooth rubbing surface without tearing.共 15 頁 第 8 頁指 導(dǎo) 教 師 評 語外文翻譯成績：指導(dǎo)教師簽字：年 月 日注：1. 指導(dǎo)教師對譯文進(jìn)行評閱時應(yīng)注意以下幾個方面：①翻譯的外文文獻(xiàn)與畢業(yè)設(shè)計（論文）的主題是否高度相關(guān)，并作為外文參考文獻(xiàn)列入畢業(yè)設(shè)計（論文）的參考文獻(xiàn)；②翻譯的外文文獻(xiàn)字?jǐn)?shù)共 15 頁 第 9 頁是否達(dá)到規(guī)定數(shù)量（3 000 字以上）；③譯文語言是否準(zhǔn)確、通順、具有參考價值。2. 外文原文應(yīng)以附件的方式置于譯文之后。0畢業(yè)設(shè)計報告( 論文)報告(論文)題目： 汽車起重機舉升機構(gòu)的 設(shè)計 作者所在系部：作者所在專業(yè)：作者所在班級：作 者 姓 名 ：作 者 學(xué) 號 ：指導(dǎo)教師姓名：完 成 時 間 ：教務(wù)處制1開題報告學(xué)生姓名 專 業(yè) 班 級指導(dǎo)教師姓名 職 稱 工作單位課題來源 橫向項目 課題性質(zhì) 結(jié)構(gòu)設(shè)計類課題名稱 汽車起重機舉升機構(gòu)設(shè)計本設(shè)計的科學(xué)依據(jù)（科學(xué)意義和應(yīng)用前景，國內(nèi)外研究概況，目前技術(shù)現(xiàn)狀、水平和發(fā)展趨勢等）舉升機構(gòu)是起升貨物并使它產(chǎn)生升降運動的機構(gòu) 它是起重機中最主要和最基本的機構(gòu)。本設(shè)計采用液壓起升機構(gòu)。油馬達(dá)經(jīng)過減速后驅(qū)動滾筒旋轉(zhuǎn)，使鋼絲繩繞進(jìn)卷筒或由卷筒放出，從而使吊鉤升降。卷筒的正反向轉(zhuǎn)動是通過改變馬達(dá)的轉(zhuǎn)向達(dá)到的而機構(gòu)運動的停止或使貨物保持在懸吊狀態(tài)是依靠棘輪停止器來實現(xiàn)的。舉升機構(gòu)包括了吊具、卷筒、減速器、制動器、電機等多方面。設(shè)計內(nèi)容和預(yù)期成果（具體設(shè)計內(nèi)容和重點解決的技術(shù)問題、預(yù)期成果和提供的形式）總體設(shè)計要求及技術(shù)要點：本文主要研究設(shè)計隨車起重運輸車舉升機構(gòu)，對舉升機構(gòu)的組成和工作原理進(jìn)行簡單闡述。主要針對卷筒和減速器做詳細(xì)的設(shè)計計算和強度校核，對于其他部件進(jìn)行簡單設(shè)計和選用。擬采取設(shè)計方法和技術(shù)支持（設(shè)計方案、技術(shù)要求、實驗方法和步驟、可能遇到的問題和解決辦法等）隨車起重機是安放在載貨汽車上的一種附加起重設(shè)備。它屬于臂架型起重機，其運行支承裝置采用氣輪胎，可以在無軌路面上行走。與其他起重機相比，隨車起重機把起重和運輸功能結(jié)合起來，不僅節(jié)省勞動力，而且節(jié)約能源、減少費用，也由于設(shè)計和制造隨車起重機的技術(shù)進(jìn)步，使其生產(chǎn)有了較大的發(fā)展。舉升機構(gòu)用于實現(xiàn)貨物的升降，它是任何起重機不可缺少的部是起重機中最重要與基本的部分。其工作的好壞，直接影響到整臺機構(gòu)的工作性能。2實現(xiàn)本項目預(yù)期目標(biāo)和已具備的條件（包括過去學(xué)習(xí)、研究工作基礎(chǔ)，現(xiàn)有主要儀器設(shè)備、設(shè)計環(huán)境及協(xié)作條件等）工作內(nèi)容及最終成果：第一部分 緒論。第二部分 舉升機構(gòu)方案選用分析。第三部分 舉升機構(gòu)基本參數(shù)計算。第四部分 舉升機構(gòu)各組成設(shè)計與選用。第五部分 技術(shù)經(jīng)濟性分析。第六部分 結(jié)論與參考文獻(xiàn)。4.預(yù)期結(jié)果繪制工程圖紙 4 張，裝配圖 2 張，A0~A1 零件圖 2 張。A1 編寫設(shè)計計算說明 1 份，翻譯相關(guān)外文文獻(xiàn) 1 篇各環(huán)節(jié)擬定階段性工作進(jìn)度(以周為單位)第 1 周—第 2 周 畢業(yè)實習(xí),收集資料,撰寫實習(xí)報告。第 3 周 撰寫開題報告 進(jìn)行開題答辯。第 4 周—第 5 周 舉升機構(gòu)的基本參數(shù)計算。第 6 周—第 7 周 鋼絲繩的設(shè)計與選用。第 8 周—第 9 周 吊鉤的設(shè)計和選用。第 10 周—第 11 周 卷筒設(shè)計。第 12 周—第 13 周 減速器設(shè)計。第 14 周 撰寫說明書。第 15 周—第 16 周 應(yīng)用計算機繪圖。第 17 周 整理設(shè)計資料 打印輸出 提交設(shè)計資料。第 18 周 準(zhǔn)備答辯 論文評閱。第 19 周 畢業(yè)設(shè)計答辯。3開 題 報 告 審 定 紀(jì) 要時 間 地點 主持人姓 名 職 務(wù)（職 稱） 姓 名 職 務(wù)（職 稱）參會教師論證情況摘要記錄人：指導(dǎo)教師意見指導(dǎo)教師簽名： 年 月 日教研室意見 教研室主任簽名： 年 月 日4