Equation F.21. Combination of 2 centre-handle turning-locks Z₁, Z₂ with sprint action

Equation F.22. Combination of 2 centre-handle turning-locks Z₃, Z₄ with spring action

Equation F.23. Combination of 2 latches K , M; 2 centre-handle turning-locks Z₃, Z₄

Equation F.24. Turning-lock a

Turning-lock a to right

Equation F.25. Catch b

Equation F.26. Chains C₁, C₂, C₃

Curve 51. Chain C₁, inclined.
Curve 52. Chain C₂, vertical.
Curve 53. Chain C₃, horizontal.

Equation F.27. Door strap without pawl d₁, with pawl d₂

Curve 54. Door strap without pawl d₁
Curve 55. Door strap with pawl d₂

Equation F.28. Sliding bolt Y₁ with pawl Y₂

Equation F.29. 2 door straps, 2 pawls — d₂, d₄

Equation F.30. Door strap d₃ and sliding bolt Y₃

Curve 58. Door strap with unlocked padlock d₃
Curve 59. Sliding bolt with unlocked padlock Y₃