gearbox.standards.agma2101._factors

Influence factors of AGMA 2001-D04 other than the geometry factors.

dynamic_factor(transmission)

Dynamic factor K_v, AGMA 2001-D04 annex A, formulae (A.1) to (A.3).

K_v = ((A + sqrt(v_t)) / A)^B with B = 0.25 (12 - Q_v)^0.667, A = 50 + 56 (1 - B) and v_t the pitch line velocity in ft/min. Q_v is limited to 5..11 (A.2).

Parameters:

transmission (Transmission) – The gear pair. agma_quality_number selects Q_v; if None the lower of the values estimated for pinion and wheel is used.

Returns:

The dynamic factor (>= 1).

Return type:

float

size_factor(transmission)

Size factor K_s (AGMA 2001-D04, clause 18), interpolated on the module.

Parameters:

transmission (Transmission) – The gear pair.

Returns:

The size factor.

Return type:

float

load_distribution_factor(transmission)

Load distribution factor K_m = 1 + C_mc (C_pf C_pm + C_ma C_e) (clause 16).

Parameters:

transmission (Transmission) – The gear pair.

Returns:

The load distribution factor.

Return type:

float

rim_thickness_factor(gear)

Rim thickness factor K_B of one gear, AGMA 2001-D04 annex B (B.1 and figure B.1).

m_B = t_R / h_t; K_B = 1 for m_B >= 1.2 and 1.6 ln(2.242 / m_B) below. For a gear without a specified rim (solid disc) the radial thickness under the root is (d_f - d_shaft) / 2.

Parameters:

gear (Gear) – The gear.

Returns:

The rim thickness factor.

Raises:

ValueError – If the backup ratio is 0.5 or less (needs a special analysis, B.2).

Return type:

float