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Five Hundred and Seven Mechanical Movements - North, Dug_7

Tham khảo tài liệu 'five hundred and seven mechanical movements - north, dug_7', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Simpo PDF Merge and Split Unregistered Version - http www.simpopdf.com Mechanical Movements. 79 313. Chronometer escapement the form now commonly constructed. As the balance rotates in the direction of the arrow the tooth V on the verge presses the passingspring against the lever pressing aside the lever and removing the detent from the tooth of the escape-wheel. As balance returns tooth presses aside and passes spring without moving lever which then rests against the stop E. p is the only pallet upon which impulse is given. 314. Lever chronometer escapement. In this the pallets. A B and lever look like those of the lever escapement 376 but these pallets only lock the CSCA e-wheel. having no impulse. Impulse is given by teeth of escape-wheel directly to a pallet c attached to balance. 315. Conical pendulum hung by a thin piece of round wire. Lower end connected with and driven in a circle bv an arm attached to a vertical rotating spindle. The pendulum-rod describes a cone in its revolution. 316. Mercurial compensation pendulum. A glass jar of mercury is used for the bob or weight. As the pendulumrod is expanded lengthwise by increased temperature the expansion of mercury in jar carries it to a greater height therein and so raises its center of gravity relatively to the rod sufficiently to compensate for downward expansion of the rod. As rod is contracted by a reduction of temperature contraction of mercury lowers it relatively to rod. In this way the center of oscillation is always kept in the same place and the effective length of pendulum alwavs the same. 317. Compound bar compensation pendulum c is a compound bar of brass and iron or steel brazed together with brass downward. As brass expands more than iron the bar will bend upward as it gets warmer and carry the weights w w up with it raising the center of the aggregate weight M w to raise the center of oscillation as much as elongation of the pendulum rod would let it down. 31S. Watch regulator. The .