coal, for instance.
A hammer in which the weight is raised by the power of machinery.
There are several varieties, which differ in construction or mode of application.
See list under hammer.
Fig. 3930 may stand as an example of a form of power-hammer, made of various sizes from that of heavy forging to the small hammer for jewelers.
The power is communicated by a friction pulley.
The belted pulley is loose on the shaft, and the friction pulley slides on a spline on the shaft.
The operator bears down with his foot upon the treadle, which passes around the hammer; this brings the friction in contact with the belted pulley, which is running all the time, and rotates the shaft, on which is a crank; this, by means of a connecting rod and spring, works the hammer, giving a blow depending for its str
34,932WilliamsApr. 8, 1862.
38,450PalmerMay 5, 1863.
45,236FolsomNov. 29, 1864.
109,427LandfearNov. 22, 1870.
109,655PalmerNov. 29, 1870.
110,945WoodwardJan. 10, 1871.
106,092StrainAug. 2, 1870.
109,753PalmerNov. 29, 1870.
110,480LloydDec. 27, 1870.
Apr. 21, 1863.
38,658DaleMay 26, 1863.
38,837PalmerJune 9, 1863.
38,927CookJune 16, 1863.
(Reissue.)6,005RoseAug. 11, 1874.
161,632PalmerApr. 6, 1875.
13,275RobinsonJuly 16, 1869.
102, 294MellenApr. 26, 1870.
118,145PalmerAug. 15, 1871.
119,496BartlettOct. 3, 1871.
1g of the ordinary Sewing-Machine. No. 124,694, Palmer, March 19, 1872, machine for sewing pamphlets.
No. 135,662, Palmer, February 11, 1873, booksewing-machine.
The signature, held between two slottNo great improvements in speed were made until Palmer, who, according to De Quincey, was twice as grmers and Ogle, Boase and Rawe, Heaton, Napier, Palmer, Gibbs and Applegath, Church, Redmund, Squire