Complete interchange assembles a law (1) definition: In overall product, when assembling, each composition annulus does not need to choose or do not need to change its size or position, the outfit that assembles precision requirement can be achieved to match a method namely after assembling, call complete interchange way. (2) characteristic: Advantage: Assemble quality stable and reliable (assembling quality is the treatment that relies on a spare parts precision will assure) ; Rig a process simple, assemble efficiency tall (the spare parts does not need to choose, do not need to repair grind) ; Come true to be assembled automatically easily, facilitating organization flow operation; Product maintenance is convenient. Insufficient place: Should assemble precision the demand is higher, count in compositive annulus especially relatively a long time, the production public errand that forms link sets severely, the spare parts creates difficulty, finished cost is high. (3) application: Complete interchange assembles a law to apply to producing group by group, mass-produced traditional Chinese clothes matchs those to comprise annulus to count less or although compositive annulus number is much but assemble the machine structure with precision not high demand. (Public errand of the spare parts when standard of 4) complete interchange assembles decides really: 1) seal closed circuit certainly: Sealing closed circuit is the precision after the product is assembled, its should satisfy the technical requirement of the product. Seal the tolerancepublic errand T0 of closed circuit to be decided by the precision of the product. 2) find out all composition annulus, the picture assembles dimension catenary graph: The basis assembles dimension chain establish a method, begin to search all composition annulus by the one aspect of the matter that seals closed circuit, draw next assemble dimension catenary graph. 3) school nucleus the basic measure of each annulus: The basic measure of each annulus must satisfy requirement leaving type: Ao= Σ Ai - the basic measure that Σ Ai seals closed circuit namely is equal to all adding all the basic measure the sum of annulus is subtractive decreasing the basic measure the sum of annulus. 4) the public errand that decides each form link: The public errand that forms link each must satisfy the requirement of next type: Ti of To ≥ Σ comprises the tolerancepublic errand the sum of annulus not to allow to be more than the public errand that seals closed circuit each namely. The Tp of average public errand that forms link each can press type decides: In Tp=To/m type: M----To comprise annulus number. The allocation that comprises annulus public errand each should consider the following factor: A) aperture is machined harder than the axis, the tolerancepublic errand choice that the public errand of aperture should compare an axis is a few bigger; For example: Aperture, axis cooperates H7/h6. B) the part with large size is machined harder than the part with small size, the public errand of large size part is taken a few bigger; C) compositive annulus is standard component dimension when, value of its public errand is certain value, can inquire in relative standard. 5) the extreme deviation that decides each form link: A) first make choice of comprises annulus to serve as harmonious annulus: Harmonious annulus chooses to be machined easily and measure spare parts size commonly; B) include dimension (like aperture) by base aperture makes decide its extreme deviation: Leave error namely for 0; C) dimension be includinged (like the axis) make by basic shaft decide its extreme deviation: Go up namely deviation is 0. 6) those who coordinate the extreme deviation of annulus is affirmatory: The computation of deviation is formulary among the basis: I of △ of △ 0= Σ - in type of Σ △ J: △ 0---To seal the intermediate deviation of closed circuit, △ 0= (ES0+EI0) / 2; J of △ of Σ △ I, Σ---It is all all intermediate deviation the sum that add annulus, intermediate deviation the sum that reduce annulus respectively. Beg the intermediate deviation of a harmonious annulus, beg a fluctuation deviation to be by the public errand of harmonious annulus again: ES= △ + T/2 EI= △ - T/2 application citing: Following plan institute show the assembly of gear component, the axis is fixed immobile, gear above rotate, the axial clearance of requirement gear and back-up ring is 0.
1 ～ 0.
35. Foregone: A1=30mm, a2=5mm, a3=43mm, a4=30-0.
05 Mm (standard component) , a5=5mm. Use complete interchange standard to assemble now, try to comprise the public errand of annulus and extreme deviation each certainly. Solution: (1) seal closed circuit certainly: A0 of the dimension in the graph is the dimension that after assembling, assures secondhand, also be to assemble precision requirement, so A0 is a closed circuit. (2) search each to form link by deal annulus, the picture assembles dimension catenary graph: Nextpage (3) school nucleus the basic measure of each annulus: A0= A3 - (A1+ A2+A4+ A5) =43 - (30+5+3+5) =0 is knowable the size that forms link each is exact without by accident. (4) the public errand that forms link each certainly: Calculate first the Tp of average public errand that forms link each: Tp=T0/m because: A0=3+0.
10 Mm, so: T0=0.
25mm. M=5, comprise annulus number namely. Reason: Tp=T0/m=0.
05mm and A4 is standard component, value of its public errand is certain value, its value is T4=0.
05mm. According to the difficult easy degree of treatment choice public errand is T1=0.
03mm (5) the extreme deviation that forms link each certainly: Because A5 is spacer, be machined easily and measure, reason chooses A5 to be harmonious annulus. A1, A2 is outside dimension, make affirmatory extreme deviation by basic shaft: A1=30 0-0.
04A3 is inside dimension, by base aperture makes affirmatory extreme deviation: A3=43+0.
070 (6) those who coordinate the extreme deviation of annulus is affirmatory: Seal the intermediate deviation of closed circuit to be: △ 0=(0.
The intermediate deviation of annulus of 225 each composition is: △ 1=(0-0.
2=(0-0 of 03 △ .
3=(0 of 02 △ .
4=(0-0 of 035 △ .
05)/2=- - 0.
025 by: △ 0= △ 3 - (1+ △ of △ 4+ △ 5) gets 2+ △ : △ 5= △ 3 - (1+ △ of △ 4+ △ of 2+ △ 0)=0.
035 - (- - 0.
225)=- - 0.
The extreme deviation of A4 of 115 harmonious annulus is: ES= △ 5+T5/2=- - 0.
10EI= △ 5- T5/2=-0.
13 have so: A5=5-0.
Statistical crossing-over assembles a law (not complete interchange assembles a law) with complete interchange the law is assembled, assemble although the process is simple, but it is the basis adds annulus, decrease annulus at the same time case of occurrence extreme value builds the dimension between a closed circuit and compositive annulus to concern, the production public errand that because form link,shares crosses Xiaochang to make the spare parts machines generation difficulty. Complete interchange standard machines precision to exchange complete interchange to assemble for cost with raising a part is wasteful sometimes. Statistical crossing-over assembles a law to say not complete interchange assembles a law again, it is to will comprise the production public errand of annulus to magnify appropriately character actually, make the spare parts is machined easily, but this meets those who make seldom count a product assemble precision to exceed a regulation to ask, but this kind of incident is small probability incident, happen rarely. Comprise annulus amount especially less, goods lot is many, from total economic effect analysis, remain economy feasible. The advantage of law of recipe of transhipment of through cargo of statistical each other is: Expanded to comprise the production public errand of annulus, spare parts production cost is low; Rig a process simple, manufacturing efficiency is tall. Insufficient place is: There is what seldom count provision of product short of to assemble precision to ask after assembling, must take another repair step. Recipe law applies to the large transhipment of through cargo that count each other to match those assembly in large quantities of mass-produced traditional Chinese clothes precision demand is higher and compositive annulus is counted much machine structure. 2, the choice assembles a law 1, the choice assembles a law to define: The public errand that is annulus of the composition in will assembling dimension chain magnifies the degree with feasible economy, choose equal part to undertake constructional next, the outfit recipe law that asks with assuring to assemble precision, call a choice to assemble a law. Comfortable use closes: Assemble precision the demand is high, and compositive annulus is less group by group or big batch production. 2, the choice assembles law sort to choose directly match a law: (1) definition: When assemble, worker from a lot of waiting for in constructional part, choose equal part to undertake constructional directly, the choice that asks with assuring to assemble precision assembles a law, call choose directly match a law. (2) characteristic: 1) assemble precision taller; 2) when assembling, measure by experience and judgement sex will select a part, assemble time not easy and accurate control; 3) assemble precision to depend on greatly technical level of the worker. Choose in group match a law: (1) definition: The public errand that forms each link begs numeric enlarge relative to place of complete interchange standard multiple, make its can be machined by economical accuracy, press again measure dimension general part actually in group, do not undertake constructional by corresponding constituent, the choice that assembles precision requirement in order to achieve assembles a law, call choose in group match a law. (2) application: Be in large quantities of mass-produced in, assemble those precision requirements not to facilitate particularly high again at the same time the part that uses adjusting gear, if use crossing-over to assemble a law, the production common difference that forms link is too little, very difficult or treatment is very wasteful, can use right now choose in group match a law to assemble. (3) choose the general requirement that matchs a law in group: 1) use in group the law is assembled best can make distributinging curve has the measure of two-phase fittings identical symmetrical distributinging curve, if dimension distributinging curve is not identical or asymmetry, will cause each groups of suitable parts number differs and cannot complete form a complete set, create waste. 2) use in group when the law is assembled, of the spare parts count in group unfavorable and too much, can measure because of the spare parts otherwise, the accretion of classification, custodial, carriage workload and make production organizes the job to become quite complex. (4) in group the characteristic that the law assembles: Main good point is: The production precision of the spare parts is not tall, but can obtain very tall assembly however precision; Inter block spare parts is OK crossing-over, assemble efficiency tall. Insufficient place is: Increased a spare parts to measure, in group, put lay aside, carriage workload. Assemble a law to apply to in group those composition match in large quantities of mass-produced traditional Chinese clothes annulus number is little and assemble precision to ask again particularly high machine structure. 3, fitting assembly method 1, definition: Be in will assembling dimension chain, each comprise annulus to machine precision to make by economy, when assembling, the constitutes annulus measure method that adopts predefine of the some in changing dimension cable length will assure those who assemble precision to assemble a law, call fitting assembly method. When using law of make repairs and supply replacements to assemble, each composition annulus all produces the accuracy class treatment with the feasible economy below the condition by this, the error that annulus place accumulates closes when assembling, the assembly that will naturally exceed a regulation precision requirement; The assembly to obtain a provision precision, the dimension of annulus of some one composition in make repairs and supply replacements is being needed to assemble dimension chain when assembling (this composition annulus calls) of annulus of make repairs and supply replacements. To reduce workload of make repairs and supply replacements, the compositive annulus that should choose those facilitating to undertake make repairs and supply replacements makes ring of make repairs and supply replacements. When using law of make repairs and supply replacements to assemble, annulus of requirement make repairs and supply replacements must stay have enough but not be amount of too large make repairs and supply replacements. 2, the characteristic of fitting assembly method: Main good point is: Compositive annulus all can machine economical accuracy to make, but can obtain very tall assembly however precision. Insufficient place is: Increased workload of make repairs and supply replacements, manufacturing efficiency is low; Tall to assembling technical level of the worker to ask. 3, application: Fitting assembly method applies to sheet pre production traditional Chinese clothes matchs those composition annulus number is more and assemble precision to ask again higher machine structure. 4, adjust assemble a law 1, definition: When assembling, adjust with the change a relative position in machine structure or choose adjust suitably will achieve the outfit recipe standard that assembles precision, call tone to get ready match a law. Adjust the principle that assembles law and fitting assembly method basic and identical. In asking to be those who seal closed circuit to build to assemble dimension chain with assembling precision, except outside adjusting annulus, each comprise annulus to all be made in order to machine economical accuracy, because enlarge compositive annulus to make tolerancepublic errand accumulate a closed circuit that cause to cross big error, adjust through adjusting (or say to compensate) the method of relative position is eliminated, achieve finally assemble precision requirement. Adjust the method that adjusts a relative position has movable setting method, fixed setting method and error quits setting method 3 kinds. 2, adjust the characteristic that assembles a law: Main good point is: Compositive annulus all can machine economical accuracy to make, but can obtain taller assembly however precision; Assemble efficiency taller than fitting assembly method. Insufficient place is to want to increase an adjusting gear additionally. 3, application: Quits setting method applies to movable setting method and error to apply in pre production, fixed setting method basically applies to large quantities of quantities to produce. CNC Milling