. Journal of electricity, power, and gas . e the pitch the pitch circle the distance (d) is called theworking depth of the tooth, and equals (2a). An addi-tional space (f), the clearance, is provided to preventthe top of the tooth from coming in contact with thei)ottom of the space which it occupies in the othergear. The thickness of the tooth is (i) ; the jiirch diam-eter D: and the outside diameter D. The addendum (a) is ordinarily chose, i equal to -r-, thus permits the following relations which may be shown mathematically: (1) a = .318? the addendum. N + 2 To use the table it i
. Journal of electricity, power, and gas . e the pitch the pitch circle the distance (d) is called theworking depth of the tooth, and equals (2a). An addi-tional space (f), the clearance, is provided to preventthe top of the tooth from coming in contact with thei)ottom of the space which it occupies in the othergear. The thickness of the tooth is (i) ; the jiirch diam-eter D: and the outside diameter D. The addendum (a) is ordinarily chose, i equal to -r-, thus permits the following relations which may be shown mathematically: (1) a = .318? the addendum. N + 2 To use the table it is necessary to draw the pitchcircles and then the circles of face and tlank centersat distances inside of or outside of the pitch circlecorresponding to the values given. Thus in a 20-tnoth pinion the centers for drawing the tooth faceswould lie on a circle whose radius would be .13 inchesless than the radius of the pitch circle, while the flankcur\e centers would fall on a larger circle, the radius (2) D (3) 2a + f^ the outside the total depth of space. These formulae give the necessary data to enablethe machinist to proceed with the actual cutting ofthe teeth. N The formula P ? D gives the relations between size, pitch, and number of teeth. Knowing P and Nthe second formula gives the overall diameter of thedisc when turned ready for cutting the teeth. Thelast formula gives the depth of the cut into the now the machinist is provided with the propertemplate and has worked out the number of teeth,etc., he can proceed with the actual cutting of theteeth. of which would be inches greater dtia the ])itchcircle radius. Having drawn these circles the toothintervals may be laid out on the pitch circle and thenwith the radius as indicated and centers on the flankcircle, the flank curves may all be drawn in; with cor-responding face radius and centers on the inner face centers are then drawn from the pitch circleout to the outer circle. It is to
Size: 1850px × 1351px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, bookidjo, booksubjectelectricity
