盤角齒輪盤角齒輪及鉆孔夾具設(shè)計(jì)
盤角齒輪盤角齒輪及鉆孔夾具設(shè)計(jì),齒輪,鉆孔,夾具,設(shè)計(jì)
盤角齒輪加工工藝及鉆孔夾具設(shè)計(jì)
（文獻(xiàn)綜述）
[1].金屬切削手冊[M]，上海金屬切削技術(shù)協(xié)會編：上海科學(xué)技術(shù)出版社，1984
切削用量的合理選擇
在確定了刀具幾何參數(shù)后，還需選定切削用量參數(shù)才能進(jìn)行切削加工。目前許多工廠是通過切削用量手冊，實(shí)踐總結(jié)或工藝實(shí)驗(yàn)來選擇切削用量。制定切削用量時(shí)應(yīng)考慮加工余量，刀具耐用度、機(jī)床功率、表面粗糙度、刀具刀片的剛度和強(qiáng)度等因素。
１．粗車切削用量的選擇
對于粗加工，在保證刀具一定耐用度前提下，要盡可能提高在單位時(shí)間內(nèi)的金屬切除量，提高切削用量都能提高金屬切削量，但是考慮到切削用量對刀具耐用度的影響程度，所以，在選擇粗加工切削用量時(shí)，應(yīng)優(yōu)先選用大的背吃刀，其次選較大的進(jìn)給量，最后根據(jù)刀具耐用度選定一個合理的切削速度，這樣選擇可減少切削時(shí)間，提高生產(chǎn)率。背吃刀量應(yīng)根據(jù)加工余量和加工系統(tǒng)的剛性確定。
２．精加工切削用量的選擇
選擇精加工或半精工切削用量的原則是在保證加工質(zhì)量的前提下，兼顧必要的生產(chǎn)率。進(jìn)給量根據(jù)工件表面粗糙度的要求來確定。精加工時(shí)切削速度的切削速度應(yīng)避開積屑瘤區(qū)，一般硬質(zhì)合車刀采用高速切削。
孔加工刀具的種類和用途
孔加工刀具按其用途可分為兩大類：一類是鉆頭，它主要用于在實(shí)心材料上鉆孔(有時(shí)也用于擴(kuò)孔)。根據(jù)鉆頭構(gòu)造及用途不同，又可分為麻花鉆、扁鉆、中心鉆及深孔鉆等；另一類是對已有孔進(jìn)行再加工的刀具，如擴(kuò)孔鉆、鉸刀及鏜刀等。
（一）麻花鉆
麻花鉆是一種形狀復(fù)雜的孔加工刀具，它的應(yīng)用較為廣泛。常用來鉆精度較低和表面較粗糙的孔。用高速鋼鉆頭加工的孔精度可達(dá)IT11～I(xiàn)T13，表面粗糙度可達(dá)6.3～25；用硬質(zhì)合金鉆頭加工時(shí)則分別可達(dá)IT10～I(xiàn)T11和3.2～12.5。
（二）中心鉆
中心鉆用于加工中心孔。有三種形式：中心鉆、無護(hù)錐60°復(fù)合中心鉆及帶護(hù)錐60°復(fù)合中心鉆。中心鉆在結(jié)構(gòu)上與麻花鉆類似。為節(jié)約刀具材料，復(fù)合中心鉆常制成雙端的。鉆溝一般制成直的。復(fù)合中心鉆工作部分由鉆孔部分和锪孔部組成。鉆孔部與麻花鉆同樣，有倒錐度及鉆尖幾何參數(shù)。锪孔部制成60°錐度，保護(hù)錐制成120°錐度。復(fù)合中心鉆工作部分的外圓須經(jīng)斜向鏟磨，才能保證锪孔部和锪孔部與鉆孔部的過渡部分具有后角。
（三）深孔鉆
一般深徑比(孔深與孔徑比)為5～10的孔即為深孔。加工深徑比較大的深孔可用深孔鉆。深孔鉆的結(jié)構(gòu)有多種形式，常用的主要有外排屑深孔鉆、內(nèi)排屑深孔鉆、噴吸鉆等等。
（四）擴(kuò)孔鉆
擴(kuò)孔鉆用于已有孔的擴(kuò)大，一般加工精度可達(dá)IT10～I(xiàn)T11，表面粗糙度可達(dá)3.2～12.5，通常作為孔的半精加工刀具。擴(kuò)孔鉆的類型主要有兩種，即整體錐柄擴(kuò)孔鉆和套式擴(kuò)孔鉆。
（五）锪鉆
锪鉆用于加工各種埋頭螺釘沉頭座、錐孔、凸臺面等。
[2] 機(jī)械加工工藝手冊第1卷[M] .孟少龍編 機(jī)械工業(yè)出版社，1991
一、基準(zhǔn)的概念及分類
零件上用以確定其它點(diǎn)、線、面的位置所依據(jù)的那些點(diǎn)、線、面稱為基準(zhǔn)。根據(jù)其功用的不同，可分為設(shè)計(jì)基準(zhǔn)、工藝基準(zhǔn)兩大類。
(一)設(shè)計(jì)基準(zhǔn)
在零件圖上用以確定其它點(diǎn)、線、面的基準(zhǔn)，稱為設(shè)計(jì)基準(zhǔn)。
(二)工藝基準(zhǔn)
零件在加工、測量、裝配等工藝過程中使用的基準(zhǔn)統(tǒng)稱工藝基準(zhǔn)。工藝基準(zhǔn)又可分為：
1．裝配基準(zhǔn) 在零件或部件裝配時(shí)用以確定它在機(jī)器中相對位置的基準(zhǔn)。
2．測量基準(zhǔn) 用以測量工件已加工表面所依據(jù)的基準(zhǔn)。例如以內(nèi)孔定位用百（千）分表測量外圓表面的徑向跳動，則內(nèi)孔就是測量外圓表面徑向跳動的測量基準(zhǔn)。
3．工序基準(zhǔn) 在工序圖中用以確定被加工表面位置所依據(jù)的基準(zhǔn)。所標(biāo)注的加工面的位置尺寸稱工序尺寸。工序基準(zhǔn)也可以看作工序圖中的設(shè)計(jì)基準(zhǔn)。圖6-1 所示為鉆孔工序的工序圖，圖a、b分別表示兩種不同的工序基準(zhǔn)和相應(yīng)的工序尺寸。
4．定位基準(zhǔn) 用以確定工件在機(jī)床上或夾具中正確位置所依據(jù)的基準(zhǔn)。如軸類零件的中心孔就是車、磨工序的定位基準(zhǔn)。如圖6-2所示的齒輪加工中，從圖a可看出，在加工端面E及內(nèi)孔F的第一道工序中，是以毛坯外圓面A及端面B確定工件在夾具中的位置的，故A、B面就是該工序的定位基準(zhǔn)。圖b是加工齒輪端面B及外圓A的工序，用E、F面確定工件的位置，故E、F面就是該工序的定位基準(zhǔn)，由于工序尺寸方向的不同，作為定位基準(zhǔn)的表面也就不同。
作為基準(zhǔn)的點(diǎn)、線、面有時(shí)在工件上并不一定實(shí)際存在（如孔和軸的軸線、某兩面之間的對稱中心面等），在定位時(shí)是通過有關(guān)具體表面起定位作用的，這些表面稱定位基面。例如在車床上用頂尖撥盤安裝一根長軸，實(shí)際的定位表面（基面）是頂尖的錐面，但它體現(xiàn)的定位基準(zhǔn)是這根長軸的軸線。因此，選擇定位基準(zhǔn)，實(shí)際上既選擇恰當(dāng)?shù)亩ㄎ换妗?
二、定位基準(zhǔn)的選擇原則
根據(jù)定位基面表面狀態(tài)，定位基準(zhǔn)又可分為粗基準(zhǔn)和精基準(zhǔn)。凡是以未經(jīng)過機(jī)械加工的毛坯表面作定位基準(zhǔn)的，稱為粗基準(zhǔn)，粗基準(zhǔn)往往在第一道工序第一次裝夾中使用。如果定位基準(zhǔn)是經(jīng)過機(jī)械加工的，稱為精基準(zhǔn)。精基準(zhǔn)和粗基準(zhǔn)的選擇原則是不同的。
(一)粗基準(zhǔn)的選擇
粗基準(zhǔn)的選擇，主要考慮如何保證加工表面與不加工表面之間的位置和尺寸要求，保證加工表面的加工余量均勻和足夠，以及減少裝夾次數(shù)等。具體原則有以下幾方面：
1．如果零件上有一個不需加工的表面，在該表面能夠被利用的情況下，應(yīng)盡量選擇該表面作粗基準(zhǔn)。
2．如果零件上有幾個不需要加工的表面，應(yīng)選擇其中與加工表面有較高位置精度要求的不加工表面作第一次裝夾的粗基準(zhǔn)。
3．如果零件上所有表面都需機(jī)械加工，則應(yīng)選擇加工余量最小的毛坯表面作粗基準(zhǔn)。
4．同一尺寸方向上，粗基準(zhǔn)只能用一次。
5．粗基準(zhǔn)要選擇平整、面積大的表面。
(二)精基準(zhǔn)的選擇
選擇精基準(zhǔn)時(shí)，主要應(yīng)考慮如何保證加工表面之間的位置精度、尺寸精度和裝夾方便，其主要原則是：
1．基準(zhǔn)重合原則 即選設(shè)計(jì)基準(zhǔn)作本道加工工序的定位基準(zhǔn)，也就是說應(yīng)盡量使定位基準(zhǔn)與設(shè)計(jì)基準(zhǔn)相重合。這樣可避免因基準(zhǔn)不重合而引起的定位誤差。
2．基準(zhǔn)統(tǒng)一原則 在零件加工的整個工藝過程中或者有關(guān)的某幾道工序中盡可能采用同一個（或一組）定位基準(zhǔn)來定位，稱為基準(zhǔn)統(tǒng)一原則。
3．互為基準(zhǔn)原則 若兩表面間的相互位置精度要求很高，而表面自身的尺寸和形狀精度又很高時(shí)，可以采用互為基準(zhǔn)、反復(fù)加工的方法。
4．自為基準(zhǔn)原則 如果只要求從加工表面上均勻地去掉一層很薄的余量時(shí)，可采用以加工表面本身作定位基準(zhǔn)。
[3] 機(jī)床夾具設(shè)計(jì)手冊[M]，王光斗，王春福編 上?？茖W(xué)技術(shù)出版社，2000。
第一節(jié) 專用夾具的設(shè)計(jì)方法
一、專用夾具的基本要求和設(shè)計(jì)步驟
1．專用夾具的基本要求
（1）保證工件加工的各項(xiàng)精度要求
（2）提高生產(chǎn)效率
（3）工藝性好
（4）使用性好
2．專用夾具的設(shè)計(jì)步驟
（1）明確設(shè)計(jì)任務(wù)，收集設(shè)計(jì)資料
（2）擬定夾具結(jié)構(gòu)方案，繪制夾具草圖
① 確定工件的定位及夾緊方案，設(shè)計(jì)定位及夾緊裝置。
② 確定夾具的對刀或?qū)蚍桨福⒃O(shè)計(jì)對刀或?qū)蜓b置。
③ 確定其他元件或裝置的結(jié)構(gòu)形式，如定位鍵、分度裝置、預(yù)定位裝置及吊裝元件等。
④ 確定夾具體結(jié)構(gòu)形式及夾具在機(jī)床上的安裝方式，繪制草圖。
（3）進(jìn)行必要的分析計(jì)算 如：工件加工精度高時(shí)應(yīng)進(jìn)行定位誤差、加工精度分析。
（4）繪制夾具總圖
（5）繪制夾具的零件圖
繪制總圖順序：
①用雙點(diǎn)劃線將工件的外形輪廓、定位基面、夾緊表面及加工表面畫在各視圖相應(yīng)位置上，待加工表面的加工余量可用網(wǎng)紋線或粗實(shí)線表示。在總圖中工件可看作透明體，不遮擋后面的線條。
②依次畫出定位、夾緊、對刀、導(dǎo)向元件或裝置的具體結(jié)構(gòu)，再畫出夾具體，將各元件或裝置連成一個整體。
③標(biāo)注尺寸、公差和技術(shù)要求。
④編制夾具的明細(xì)表及標(biāo)題欄。
夾具中的非標(biāo)零件都要繪制零件圖，并按總圖要求確定零件的尺寸、公差及技術(shù)要求。
[4] 機(jī)床夾具設(shè)計(jì)手冊[M]，東北重型機(jī)械學(xué)院編 上?？茖W(xué)技術(shù)出版社，1979。
二、夾具總圖尺寸及技術(shù)要求的制訂
1．夾具總圖上應(yīng)標(biāo)注的尺寸和公差
（1） 夾具外形的最大輪廓尺寸
（2） 影響定位精度的尺寸及公差
（3） 影響對刀精度的尺寸及公差
（4） 影響夾具在機(jī)床上安裝精度的尺寸及公差
（5） 影響夾具精度的尺寸和公差
（6） 其他裝配尺寸和公差
2． 夾具總圖上公差值的確定
（1）直接影響工件加工精度的夾具公差
（2）與工件上未注公差的加工尺寸對應(yīng)的夾具公差
3． 夾具總圖上應(yīng)標(biāo)注的技術(shù)要求
鉆床夾具設(shè)計(jì)特點(diǎn)
一、鉆床夾具的主要類型
鉆床夾具簡稱鉆模，主要用于加工孔及螺紋。它主要由鉆套、鉆模板、定位及夾緊裝置夾具體組成。其主要類型有以下幾種。
（1）固定式鉆模 在使用中，這類鉆模在機(jī)床上的位置固定不動，而且加工精度較高，主要用于立式鉆床上加工直徑較大的單孔或搖臂鉆床加工平行孔系。
（2）回轉(zhuǎn)式鉆模 這類鉆模上有分度裝置，因此可以在工件上加工出若干個繞軸線分布的軸向或徑向孔系。
（3）翻轉(zhuǎn)式鉆模 主要用于加工小型工件不同表面上的孔，孔徑小于f8~f10mm。它可以減少安裝次數(shù)，提高被加工孔的位置精度。其結(jié)構(gòu)較簡單，加工鉆模一般手工進(jìn)行翻轉(zhuǎn)，所以夾具及工件應(yīng)小于10 kg為宜。
（4）蓋板式鉆模 這種鉆模無夾具體，其定位元件和夾緊裝置直接裝在鉆模板上。鉆模板在工件上裝夾，適合于體積大而笨重的工件上的小孔加工。夾具、結(jié)構(gòu)簡單輕便，易清除切屑；但是每次夾具需從工件上裝卸，較費(fèi)時(shí)，故此鉆模的質(zhì)量一般不宜超過10 kg。
（5）滑柱式鉆模 滑柱式鉆模是帶有升降鉆模板的通用可調(diào)夾具。這種鉆模有結(jié)構(gòu)簡單、操作方便、動作迅速、制造周期短的優(yōu)點(diǎn)，生產(chǎn)中應(yīng)用較廣。
二、鉆模的設(shè)計(jì)要點(diǎn)
1．鉆 套
鉆套安裝在鉆模板或夾具體上，用來確定工件上加工孔的位置，引導(dǎo)刀具進(jìn)行加工，提高加工過程中工藝系統(tǒng)的剛性并防振。鉆套可分為標(biāo)準(zhǔn)鉆套和特殊鉆套兩大類。
（1）固定鉆套
（2）可換鉆套
（3）快換鉆套
（4）特殊鉆套
2．鉆模板
鉆模板用于安裝鉆套，確保鉆套在鉆模上的正確位置，鉆模板多裝在夾具體或支架上，常見的鉆模板有：
（1）固定式鉆模板
（2）鉸鏈?zhǔn)姐@模板
（3）可卸（分離）式鉆模板
（4）懸掛式鉆模板
[5]manual machining process [M], Lee Mechanical Industry Press, 1990.
Order the preparation of the machining process
Process outlined in Section I
First, the production process and process
(A) of the production process
The production process refers to the raw materials into finished the whole process. A production process including raw materials, semi-finished products, components, standard parts, tools, equipment, equipment purchase, transport, inspection, custody, special tools, special tooling, special equipment design and manufacture of production such as preparation and rough manufacturing, machining, heat treatment, surface treatment, product assembly and debugging, performance testing, and product packaging, shipping and so on.
(B) process
Direct change in the production process the production of the object shape, size, relative position and performance of the process, known as the process can be different ways to complete the process. And therefore the process can be divided into specific casting, forging, stamping, welding, machining and special processing, heat treatment, surface treatment, assembly and other processes. Mechanical processing methods, the direct object to change the processing of shape, size and surface properties, making the process of finished products, known as the machining process.
Machining process by a certain number of processes in order of composition.
1. Processes
Refers to a process or a group of workers in a workplace at the same time with one or several parts of the completion of that part of continuous process.
Division process is mainly based on place of work is changing and whether the continuous processing.
Continuous here means that the work processes required for completion of other work can not be inserted into the content, or processing stage.
Process is composed of the basic unit of the process, but also the development of production plans for the basic unit of economic accounting. Process can be broken down into installation position, the step-by-step, take the knife and other components.
2. Installation
Refers to the installation of the workpiece (or assembly unit) through the first fixture after the completion of that part of the process.
3. Public spaces
Position is defined as a fixture, the workpiece in the machine tool on the percentage of completion of each location on the part of the process.
4. Step
Step refers to the surface in the processing (or assembly of continuous surface) remains unchanged, the same processing tools and the same cutting conditions, the completion of that part of continuous processes. Step-by-step process works is the basic unit of composition.
5. Cutting
Tool is the tool relative to the workpiece surface by a cutting of that portion of the work completed. Each step may include taking a walk several times a knife or knives. Second, the role of technology and type of order
(A) the role of Process
Products or parts provided for manufacturing process and method of operation, such as the document is called the Process Technology. Process is to guide the production of production, of the rationale for the production of the main technical document processing, acceptance testing, production scheduling and making arrangements for the main basis.
(B) program and the production of the type of production
1. The production of the Program, including spare parts and the means of production, including waste products.
2. The production of type
Production management by batch or continuous production, the production scale is divided into three types, namely, one-piece production, mass production and mass production.
Third, the principle of the preparation process planning, methods and steps
(A) the preparation of the principles of Process
Nature, feasibility, reasonableness and good working conditions.
(B) the preparation of the main basis for Process
Product assembly drawings and parts diagram, program and type of production and so on.
(C) Process of preparation methods and steps
Fourth, parts of the structure of process
Refers to the structure of technology in meeting the requirements under the premise of the use of, manufacture, maintenance and economic feasibility. Parts of the process can be used in different ways to manufacture, each of the processes are determined by the characteristics of processes of evaluation of parts of the structure is based on technology. How to analyze the method of the machining process with the production of parts of the structure of technology. To sum up, available from the following analysis:
1. Parts or by the laws of some simple surfaces, such as flat, rotating surface, spiral surface, such as involute surface composition, to avoid erratic singular surface, otherwise the processing will be difficult.
2. Parts of the size of the surface should be standardized and normalized. Such as holes, screw, shaft, such as the size of standardized, normalized, to be used in standard processing tool, but also easy to meet with the standard and user-friendly processing, assembly and use of the user.
3. Parts of the surface shape should be adapted to the shape of the processing tool. Otherwise, processing will increase the difficulty.
4. As far as possible to reduce the processing area. Not only reduces the processing workload, but also to ensure good contact.
5. Parts of the structure should ensure that the introduction of processing and exit the tool.
6. Parts of the structure should be able to minimize the processing time of the number of clamping and tool changing.
7. Does not require processing should not be designed rough surface processing face, do not ask for much of the surface not designed for high-precision, small surface roughness value.
8. Should be able to accurate positioning, clamping and reliable, easy processing, easy measurements.
The basic principles of positioning the workpiece
1. Six-point rule
Any of a free rigid body in space has six degrees of freedom, namely along the space axes X, Y, Z three directions and the movement around the axis of rotation of this coordinate. The substance of the workpiece position is to restrict the freedom of the workpiece.
This shows that the workpiece close to the machine when the main table or fixture on the support of these six points, it's six degrees of freedom that all restrictions would be a complete work to determine the location.
Workpiece positioning with a reasonable distribution of the six supporting points and the positioning of the workpiece touch the base to limit the work of the six degree of freedom to fully determine the location of the workpiece, known as the "six-point rule."
Six-point set is the basic law of the workpiece positioning for the actual production, the effect is to support the role of a certain shape geometry, which used to limit the freedom of the workpiece geometry is positioning components.
2. Fully positioning, not entirely due to positioning and orientation
Processing, the workpiece six degrees of freedom is completely restricted the location of the position as full.
However, the production process does not require any type of full-targeted. Should limit the number of degrees of freedom and freedom which should be calling for a decision on processing the workpiece.
For example, in a long-axis milling on the dissolution of a two keyway, keyway processing requirements in addition to its own width, depth and length, the need to ensure that the size of groove from shaft end and the external circular groove of the symmetry axis. At this point around the axis of rotation of the workpiece do not have to limit the degree of freedom as long as the limit of five degrees of freedom that is it. Workpiece six degrees of freedom have not been completely restricted positioning phenomenon is known as incomplete. Surface grinder in the grinding of the flat plate parts is not entirely an example of positioning.
To meet the processing requirements under the premise of not using positioning is permitted. However, according to processing requirements should be limited to the degree of freedom is not allowed without restriction, and it certainly can not guarantee the processing requirements, due to the phenomenon known as positioning.
3. Phenomena have been targeted
Linkage map processing materials such as small hole at the time of the first positioning means.
Workpiece to be repeated a limited degree of freedom is called off position. Under normal circumstances should be avoided as far as possible have been targeted.
However, under certain conditions, have been targeted not only allowed, but is necessary. At this point should take appropriate measures to improve the position and orientation between the base of the positional accuracy between the components, in order to avoid interference.
Such as long-axis turning, the workpiece clamping between the top two, have been restricted by the five degrees of freedom must be limited (in addition to its axis of rotation around the outside of the degree of freedom), but in order to increase the rigidity of the workpiece, often used with the tool carrier This limits the duplication of the axis direction of the workpiece in addition to the two other than the mobile freedom, there have been targeting the phenomenon. At this point should be carefully adjusted with the tool, making it the center of the center as far as possible consistent with the top.
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