26,730. John, H. Nov. 24. Shearing; punching.-In a machine for cutting section iron &c. by shearing out a strip, in which the shearing is done in two steps in complex sections, the eccentric-driven carrier 24 for the shear blade 9 is alternately pivoted about pins 25, 26. These pins are connected together by a lever 27, Fig: 4, and are operated by a rack 43 and toothed sector driven through worm gearing from a shaft 14 driven through a friction reversing-mechanism 33, Fig. 1, actuated by a foot-lever. The eccentric 54 operating the shear-blade carrier is driven by gearing from the main shaft 30 through a one-revolution clutch operated by a handle 65. Before this handle can be operated, a pin 66a, Fig. 4, engages one of the recesses 68 in the pin 26, and so the blade can be put in action only when one of the pins engages the carrier. The carrier has grooves 51 closed at the end so that the pins can always register with the holes. The weight of the carrier is balanced by a weight 50 operating through a lever 47 and chain 44. Fig. 6 shows the blade acting on one half of a joist, the carrier being pivoted about the pin 25. The side dies 8 are connected together by gearing, and are simultaneously adjusted to suit different sizes of work by turning a handle 23. The dies are inclined so that they do not foul the blade 9, Fig. 6. The bottom die 6 is mounted on a rotatable table 10, and is turned through 180 degrees by worm gearing from the shaft 14 when the point of suspension of the blade 9 is changed. The worm gearing may be put out of engagement when rotation of the dies is not required. A hookshaped stripper 70 is pivoted to the frame of the machine, and is provided with a stop so that it cannot be forced into the blade, which it serves to protect from damage.
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