Section 9.—CAM, TAPPET, AND WIPER GEAR.
For producing, from plain circular, or reciprocating motion, variable speed or motion, also intermittent and every kind of irregular motion. Cams are either open or covered. [Nos. 131, 132, and 133] are open cams; [Nos. 137] and [138], covered cams.
[131], [132], & [133]. Three forms of the “heart” cam, for giving a regular or intermittent vertical motion to a lever end.
[134]. Crown cam for vertical shaft.
[137]. Covered heart cam.
[138]. Covered crown cam.
[139]. Wiper and lever motion.
[140]. Twisted bar with sliding bush, which travels from end to end of the bar, and being prevented from turning, causes the bar to turn on its axis to the amount of its twist.
[141]. Crank pin and slotted lever; gives a variable speed with quick return.
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[142]. Spiral radius bar for opening valve. The valve is lifted off its seat by the radial motion of the lever against the inclined radius bar.
[143]. Crank pin and slotted lever motion, with slot arranged for irregular or intermittent motion.
[144]. Eccentric and slotted arm. The pin at the top of the arm has both a vertical and horizontal motion, causing it to trace an ellipse, the pin upon which the slot runs being fixed.
[145]. Wiper and lever motion, with rubbing plate; used for Cornish valves, &c.
[146]. Stamp mill.
[147]. Scroll cam.
[148]. Crank and lever, intermittent or continuous motion.
[149]. Piston, or valve rod and lever motion.
[150]. Similar movement, but with anti-friction roller on end of lever.
[151]. Rod and lever reciprocating motion, with anti-friction roller.
[152]. Similar movement, with a socket forged in the rod and the end of lever rounded to allow for angular motion.
[153]. Diagonal disc cam, or “swash plate.”
[154]. Motion for belt shifting with dead travel at half stroke. This allows the lever to move a certain distance on each side of the centre without moving the belt shifting bar.
[155] & [156]. Sectors and bent lever, used on Cornish engine valve gear.
[157]. T lever valve motion, used in rock drills, some forms of steam engines, &c.
[158]. Four-bolt camplate, used for screwing dies, locks for fireproof safes, &c.
[159]. Slot, cam, and lever motion.
[160]. Barrel motion for musical instruments, looms, &c., in which the barrel is provided with pins or staples to lift the respective levers.
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[161]. Drum with spiral vanes of long pitch, operated by a revolving arm on a shaft at right angles to the cam shaft, used for intermittent circular motion.
[162]. Volute and lever.
[163]. Double screw, for converting circular into reciprocating motion; has a right and left hand screw thread, and a shuttle attached to the lever end shaped to fit the thread, and capable of swivelling to turn the angle for reversing.
[164]. Eccentric ring and roller motion, for converting circular into reciprocating motion.
[165]. Triangular cam. Gives three reciprocations to the sliding bar in one revolution of the cam.
[166]. Fan for giving motion to several rods or arms at one time, used for organ composition pedal movement, &c.
[167]. Crossed lever motion with inclined contact surfaces, the levers being at right angles to one another.