The program below is in EXCEL. Macro's can be disabled for this one

Email me for the program mailto:mikebull@blueyonder.co.uk

Note, Although I have checked these programs I accept no responsibility for any calculations, drawings or parts manufactured to them.

No.3 - Geometry program for a single gear, just input the known parameters in red and the rest will be calculated by the program. Figures in blue are optional

geom single - READ THE HELP SHEET FIRST - do not overwrite any black figures, they contain formulae

All dims in mm

Feature

Cell name

input / calc

INPUT REQUIRED IN RED

calculated angles in this col in radians

No. of teeth

pin

26

normal module

mn

5

normal pressure angle (deg)

npa

20

helix angle (deg)

ha

15

normal pressure angle (rad)

npar

0.34906585

helix angle (rad)

har

0.261799388

Facewidth

b

100

inspection pin/ball dia

pind

8.4

normal circular pitch

pn

15.708

trans circ pitch

pt

16.262

trans base pitch

pbt

15.218

addendum mod coefficient

admod1

0.5

topping (per side)

top1

0

nominal cutter tooth depth ( 2.25 Mn )

td

2.25

cutter tip radius

tr

1

cutter depth from PL to start of rad

sr

5.592

Tooth thinning ( for backlash with mate) min

0.1

0.1

max

0.15

0.15

MANUFACTURING DETAILS

ref dia (pcd)

rd1

134.586

addendum

add1

7.500

tip dia

td1

149.586

root dia

rt1

127.086

trans pressure angle

pat

0.360356324

involute pat

ipat

0.01645339

base circle dia.

bcd1

125.942

thk n @ rd

sn1

9.674

base helix angle

bha

0.245674211

Lead

pz

1577.964

Axial pitch

px

60.691

Additional Geometry Details

Overlap ratio, based on facewidth

1.648

1