Determine accurately the new method of helical gear helix angle

  • Time:
  • Click:91
  • source:AYOR CNC Machining
Summary: The spot exemple draw of gear of column of inclined tine solid is existing helix angle measures inaccurate issue, the article introduced to use a machine tool to undertake metrical to helical gear helix angle, computation, determine the method of helical gear helix angle accurately from this. Of 1 problem put forward to undertaking maintaining to the machine, in the process of maintenance, classics regular meeting encounters the problem that component damages, the spare parts that changes to need should undertake mapping, make. Among them the it is certain to measure existence to wear difficulty of the helix angle of helical gear, basically be measured point of view is measuring an instrument without nicety (teeth directional appearance, lead appearance, tool shows badge lens to wait) below the circumstance, accomplish accurate side quantity very hard. The commonly used method that the 2 spot measurement technique that use normally have the spot is measured to helical gear helix angle has all-purpose bevel protractor side capacity method and impress law. Side measures all-purpose bevel protractor the law is to use all-purpose bevel protractor to measure point of view between the end panel of the gear that be measured and tooth flank, because the radius that follows gear changes and the helix angle of gear changes, and of general gear alveolar narrow and small, the knife feet of all-purpose bevel protractor has certain breadth, knife feet cannot be put completely alveolar inside, the position of reference circle decides very hard. Reason angle is measured very hard accurate. Graph 1 impress law is the tine in the gear that be measured after carrying Tu Se on the head, make its roll on a piece of paper, tine stayed to carry the trace that has boiled on the head on this piece of paper, make the extension line of tine top line and auxiliary line according to impress, measure a teeth directional point of view with protractor next, the helix angle that this horn ages for gear the top is in namely (1) seeing a picture, next again according to parameter of gear other geometry, computation gives the helix angle that gear reference circle is in. Because the width of gear is general not big, the extension line that make and auxiliary line have certain width error, the hard to avoid when be being measured with protractor can have an error, and the scale of protractor is with " degree " be an unit, arrive accurately to those " cent " and " second " the measurement of angle, helpless. The helix angle that 3 new measurement technique measure a way with all-purpose bevel protractor first or impress law ages to be being measured teeth of a cogwheel supports undertakes be metricaled roughly, side measures top giving a tooth-like part of anything to hate horn coming back roughly angle civilian, deserve to hang with dividing head on all-purpose milling machine next annulus method or undertake metrical on gear-hobbing machine, in order to decide tine teeth of a cogwheel carries the helix angle of place on the head. Repass computation determines the helix angle that gear is in in reference circle. Determine of tine top helix angle determine the method is as follows: Determine to measure the approximation B that goes out to be measured to age teeth of a cogwheel carries helix angle on the head first on all-purpose milling machine, measure data to be calculated roughly according to other again next the Mn(of method extent modulus that gives gear chooses) by mark fiducial value. In type of Mn ≈ Dn/[(Z/cosba+2ha] : Z -- the tine of the gear that be measured counts Da -- the tine of the gear that be measured carries round diameter Ha on the head -- the coefficient of height of teeth top of gear is dividing head and tailstock installation on the workbench of all-purpose milling machine, install the gear that be measured the tip in dividing head and tailstock to go up with core axis again, press type chooses hang annulus: In type of Sinba of · of PmnZbd40t of × of A × C=1: A, B, C, D -- place choosing is hanged annulus tine counts 1/40 -- the drive of dividing head compares T -- the pitch of guide screw of milling machine workbench (Mm) , t=nk N -- the case that has turned on dial of milling machine workbench counts K -- the mobile egg of every case hangs workbench of Si Wan bed after round of collocation is good, the handle of jolty dividing head, dividing head and workbench can cooperate motion. 1.

Hang annulus 2.

Dividing head 3.

Dial gauge 4.

Gear 5.

Does tailstock pursue the affirmatory: of Ba" of 2 helix angle? ∨ of Qu porcelain delicious cellar or pit for storing things rainwaters in puddles the garment protects  character; Sheng Bao outskirt attacks Jing holds badger of paper of abdicate of Ju of warbler of  of ┦ of travel of ⒂ of  Cong Yin then  of Jie of  of  of an ancient drinking vessel of a pavilion or house on a terrace attacks be contrary to  is read bear fact of moisture in the soil of ┦  Song shelfs than ∩ curtain   of two of pliable but strong of brother's son of Mu of value of garment of grave of Bao of  ∨ Su is fried, calculate however (tine supports) helix angle Ba" . The I=(a/b)x(c/d) in Ba"=arcsin(pmnZ/40ti) type -- the drive that registers turbine form determines than deciding G of error compensation horn, ba and computational tine carry the actual helix angle that we carry teeth of a cogwheel of the tine that be measured on the head on the head the G needing a value between helix angle Ba is called determine the error amends part, measuring the method that measures calm error to compensate horny G is to use 100 (1000) distribute a list touch the tooth flank that the top of head is being measured to age top of teeth of a cogwheel is in to go up (2) seeing a picture. Handle of jolty dividing head, make gear rotational, make workbench mobile at the same time, the scale that the shift of workbench is apart from L to be able to go up from the dial of workbench numerates (L=nk) , in 100 (1000) can numerate on cent watch the displacement on the perpendicular way that watch head extends tine to carry corkscrewed yarn on the head measures D, the measurement after its corkscrewed yarn spreads out the principle is shown 3 times like the graph. Graph in type of 3 graphs 4tgg=d/s=d/Lcosba" G=arctg[(dcosba")/L] : S -- of the actual helix angle that the length gear after measuring paragraph of corkscrewed yarn to spread out ages the top is in determine: By the graph the 3 actual helix angle that can see gear ages the top is in are taken when Arctg[(dcosba")/L] (d>0 of ± of Ba=ba" ± G=ba" " + " date; Take when D<0 " - " date) the helix angle that gear reference circle is in decides really: According to the helix angle that the geometrical parameter of gear can derive gear is in in reference circle, according to the graph 4 have Tgb=Rtgba/Ra criterion in B=arctg[(Ra-mnha)tgba]/Ra type: R -- Ra of radius of gear reference circle -- because round radius of top of tine teeth of a cogwheel changes the reference circle diameter of a gear and blame change the reference circle diameter of a gear is equal, whether does reason gear change a helix angle to helical gear without the influence, so of its helix angle determine the method is applicable also. In determine to be installation of the gear that be measured on the workbench of gear-hobbing machine on gear-hobbing machine. Will 100 (1000) the magnetic force that distributes a list is expressed stick suck go up in hob wearing, 100 (1000) on the touchs the top of head to age in the gear that be measured the top is in tooth flank that distributes a list, by thick measured a tooth-like part of anything carries helix angle Ba on the head to choose hang annulus, choose hang annulus when as a result of use gear-hobbing machine model different, use displacement formula is not same also. Press on Y3150 gear-hobbing machine type chooses differential to hang annulus: A2 × C2=9sinbab2d2mnk presses on Y38 gear-hobbing machine type chooses differential to hang round of A2 × C2=7.

9577sinbab2d2mnk presses on Y3180 gear-hobbing machine type chooses differential to hang annulus: In type of A2 × C2=6sinbab2d2mnk: A2, B2, C2, D2 choosing deserves to hang annulus tine counts Mn -- the K of method extent modulus of the gear that be measured -- assume the head of the hob when treatment is counted (K=1 or gear-hobbing machine of the actuate after K=2) is installed, the head of watch of displacement quantity L that measures a tool carrier delays tine to carry place tooth flank on the head the displacement of perpendicular direction measures D, the helix angle Ba that decides through computation top giving a tooth-like part of anything is in next and the helix angle B that reference circle is in. The Ba" in type of Ba=ba" ± Arctg[(dcosba)/LJ] B=arctg[(Ra-mnha)tgba/Ra] -- metrical computational helix angle (the model that chooses gear-hobbing machine according to place pushs computation to reach instead by displacement formula) . 4 example the one inclined columnar gear in some machine damages (partial gear teeth of a cogwheel breaks off) , measure so that tine teeth of a cogwheel counts Z=26, tine carries round diameter Da=86 on the head.

87, tine carries helix angle Ba=16deg& on the head, d1=73 of tine root round diameter.

37, determine for more accurate ground the helix angle B of this gear, use in X62W horizontal the method that dividing head matchs on all-purpose milling machine undertakes metrical. The Mn Mn=da/[(Z/cosba)+2ha=86 of method extent modulus that decides gear according to measuring gotten parameter.

8786.

87/[(26/cos16 ° ) + 2 × 1)=2.

99 ≈ 3 anthology deserve to hang annulus by computation formula gets: 3 × of A × C=pmnZ=p × 26=370=74 × 100=3.

7042 ≈ 3.

6 × of 7bd40tsinba40 × the pitch T=6mm of guide screw of station of work of milling machine of Sin16 ° 10010020X62W, , every case shift measures K=0.

× of Ba"=arcsin(pmnZ/40ti)=arcsin(p of helix angle of 05mm affirmatory computation 6 × of × of 3 × 26/40 3.

7)=16.

0187 ° get L=35mm through measuring; D=+0.

236mm computation error compensates horny G G=arctg(dcosba"/L)=arctg(0.

236 × Cos16.

0187 ° / 35)=0.

The actual helix angle that 3713 ° gear ages the top is in the G=16 of affirmatory Ba=ba"t ± of Ba.

0187 ° + 0.

3713 ° =16.

39 ° gear (reference circle is in) the affirmatory B=arctg[(Ra-mnha)tgba/Ra]=arc[(86 of helix angle B.

87/2-3 × 1)/(86.

87/2)]/tg16.

39 ° =15.

Test and verify of 847" of ° of 313 ° =15 calculates: The tine of gear carries × of round diameter Da=mnZ/cosb+2mnha=3 on the head 26/cos15.

313 ° + 3 × of 2 × 1=86.

26)/cos15 of × of Df=(mnZ)/cosb-2mn(ha+c)=(3 of round diameter of root of 87 tine teeth of a cogwheel.

313 ° - 3 × of 2 × (1+0.

25)=73.

371 computation result and measure dimension conform to. CNC Milling