The engineer's sketch-book of mechanical movements, devices, appliances, contrivances and details employed in the design and construction of machinery for every purpose

by Thomas Walter Barber

[954]. Hinge for a door, required to lay flat against the wall at either side when open.

[955]. Hinge pin for rocking levers on a knife edge.

[956]. Door spring hinge, to return the door always to its central position; the cams press against a roller attached to the springs.

[957]. Another method, with tension springs.

[958]. Rocking bearing or knife edge, used for weighing machines, &c.

[959]. Knuckle joint, halved together; the bolt secures the two parts together.

[960]. Door spring hinge with open springs and toggle movement.

[961]. Gate hinges, with double pintle at bottom to cause the gate to return to the central position without springs.

[962]. Link hinge, for a grid or trap door, to allow it to lie flat when opened.

[963]. Bayonet joint. A common device.