Section 40.—GEARING, VARIOUS DEVICES IN.
(See also [p. 92].)
[2194]. Turn-over gear for reversing a stamp, table or platen by rack and pinion.
[2195]. Double driving motion by belt for two saws, cutters, drills, &c., so that either may be put in work at various points in a half circle of the radius of the arm.
[2196]. Sun and planet gear. A is a fixed wheel, B is keyed to the barrel shaft, C and D are cast together and run loose on a stud on the crank arm.
[2197]. Two-tooth pinion gear.
[2198]. Cam spur gear, to give similar variable movements to those given by cams.
[2199]. Motion to vary the angle of a screw propeller blade, a windmill, feathering wheel, &c., by bevel gear and a central shaft.
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Section 41.—GOVERNING AND REGULATING SPEED, &c.
(See also [p. 96].)
[2200]. Atmospheric governor. Rod A is connected to reciprocate with the engine, B is connected to the equilibrium throttle valve, C is an inlet valve for air, and D an adjustable outlet valve by which the speed is regulated. For continuous instead of intermittent action on the rod and piston B, the air pump A should force air into an intermediate chamber above the piston B by addition of a diaphragm and delivery valve.
[2201]. Gas engine pendulum governor. Hit and miss. The rocking trip C falls out of gear by its own weight when the pendulum moves so fast as to release it. The upper ball is used to adjust the motion of the pendulum to the speed required.
Crank-shaft governors. See [Section 79].
Self-regulating dampers are applied to boiler flues, and are operated by the pressure of steam, so as to regulate the draught.
Governing the speed of hoists. See [No. 1495].
[2202]. Gas engine governor. The revolving cam throws the vertical arm of the lever far enough to close the gas valve when the speed increases beyond the normal.
[2203]. Steam valve-regulator, to move a valve or other detail any fractional part of its stroke and hold it at that point. The main steam and oil cylinder valves move with the pistons. The cut-off valves are controlled by a hand lever and admit steam and oil to the same ends of their respective cylinders simultaneously; the pistons only travel till they cut off their own supply, the oil fluid preventing expansive action of the steam.
[2204]. Centrifugal ball governor, with cone wheel motion to operate the cut off.
[2204A]. Even-flow regulator or governing valve, for drawing off from a tank.
Section 43.—HOOKS, SWIVELS, &c.
(See also [p. 98].)
[2205]. Hook eye for a guy rope.
[2206]. Slip hook for pile driver, monkey, &c.
[2207]. Wire hook attachment for electric wires.
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[2208]. Loop or eye shackle.
[2209]. Swivel shackle for guy, rod, or hook.
[2210]. Slip hook.
Section 44.—INDICATING SPEEDS, &c.
(See also [p. 100].)
Indicators are employed—
To register the entry and exit of workmen to or from a factory;
To register speeds and variation of load, steam pressure, &c., on an engine;
To register wind pressure, barometric variations—rainfall, sunshine, &c.;
To register periodical visits of a watchman or other official, and the hours of such visits;
To register visits to a bank safe.
[2211]. Indicator to register the flow of water by its speed and pressure against a floating ball, which actuates a pencil moving vertically against a paper cylinder which is kept revolving slowly by clockwork.