(BQ) Part 2 book "Mechanisms and mechanical devices" has contents: Latching, fastening, and clamping devices and mechanisms; spring and screw devices and mechanisms; chain and belt devices and mechanisms; computer aided design concepts; rapid prototyping; new directions in mechanical engineering,. and other contents. | CHAPTER 9 LATCHING, FASTENING, AND CLAMPING DEVICES AND MECHANISMS SIXTEEN LATCH, TOGGLE, AND TRIGGER DEVICES Diagrams of basic latching and quick-release mechanisms. Fig. 3 A latch and cocking lever is spring-loaded so that latch movement releases the cocking lever. The cocked position can be held indefinitely. Studs in the frame provide stops, pivots, or mounts for the springs. Fig. 1 Cam-guided latch (A) has one cocked, and two relaxed positions, (B) Simple overcenter toggle action. (C) An overcenter toggle with a slotted link. (D) A double toggle action often used in electrical switches. Fig. 2 An identically shaped cocking lever and latch (A) allow their functions to be interchangeable. The radii of the sliding faces must be dimensioned for a mating fit. The stepped latch (B) offers a choice of several locking positions. 230 Fig. 4 A latch mounted on a cocking lever allows both levers to be reached at the same time with one hand. After release, the cocking spring initiates clockwise lever movement; then gravity takes over. Fig. 5 A disk-shaped cocking has a tension spring resting against the cylindrical hub. Spring force always acts at a constant radius from the lever pivot point. Fig. 6 A sleeve latch (A) as an L-shaped notch. A pin in the shaft rides in a notch. Cocking requires a simple push and twist action. (B) The Latch and plunger depend on axial movement for setting and release. A circular groove is needed if the plunger is to rotate. Fig. 8 In this overcenter lock (A) clockwise movement of the latching lever cocks and locks the slide. A counterclockwise movement is required to release the slide. (B) A latching-cam cocks and releases the cocking lever with the same counterclockwise movement as (A). Fig. 7 A geared cocking device has a ratchet fixed to a pinion. A torsion spring exerts clockwise force on the spur gear; a tension spring holds the gar in mesh. The device is wound by turning the ratchet handle counterclockwise, which in turn .
