180,241. Simmons, L. H. July 14, 1921. Grates and fire-bars.-A grate for stationary or locomotive boilers is built up (to any size desired) of sections adapted to be rocked simultaneously, excepting the sections nearest the front end of the grate, and has clinker-breakers operating in each section. As shown in Figs. 1, 2, and 3, a central grate support 4 extending from the front wall 3 to the rear wall 2 divides the grate lengthways into two similar units A and B, each of which is divided into six sections, the front section being fixed, while the remainder are adapted to be rocked simultaneously. The tiltable grateframes 25 are rectangular in shape and are supported by notches 33 in their side walls 27 engaging trunnions 10, 13 on the side and centre supports 7, 4. The notch 33 is to one side of the median line of the grate-frame 25, so that the frames may be easily tilted to their dumped position. The fire-bars 45, 52 are notched at their ends to engage flanges 34, 35 on the end walls 28, 29 of the grate-frames, portions 35<1> of said flanges being cut away to allow of the insertion of the bars. The fire-bars 52 at the side of the grate are made of greater thickness than the remainder to protect the side walls of the furnace from the heat. A yoke 31 extends from the under surface of the front and rear walls of the grate-frames and carries a lug 32 so that an operating-bar 42 may be secured thereto. The stationary frame 26 is of similar construction to the tiltable frames 25, but has two notches 38 on each side wall 30 engaging trunnions 12, 14. Each unit of five tiltable grate-frames is operated manually by a lever 44 freely mounted on a shaft 21 and connected to a bar 43, the said bar 43 operating the bar 42 connected to the lugs 32 on the yokes 31. Clinker-breakers 53, 76 are provided at every third or fourth bar to rake the fire bed and break up the molten clinker. These clinker-breakers have their upper surfaces concave so that a space 61 is formed below the firebars to prevent choking of the bars. The body of the clinker-breakers is enlarged and extends downwardly so that it will not rise above the level of the fire-bars in the operated position, and thus cause jamming, and also so that the weight of the clinker-breaker will cause it to return to its r.ormal position. The clinker-breakers 53 are mounted on a rocker arm 63 which is provided with trunnions 64 at its ends, resting in notches 40 of the grate frames 25. The rocker arm 63 consists of a web 65 and a rectangular head 66, and engages a rectangular opening and a slot 58 in the shank of the clinker-breaker. Portions 67 are cut away from the rectangular head 66 so that the clinker-breakers may be slid into position. Similar clinker-breakers are provided in the fixed grate-frame, but work in a reversed direction. The clinker-breakers of the five tiltable frames are connected by a bar 71 attached to an arm 69 on the rocker bar 63 and operated by a bar 73 connected to a lever 74 mounted on the shaft 21. The rocker bar 75 of the clinker-breaker 76 is similarly connected to the shaft 21 by a bar 77 and a lever 78. The shaft 21 is oscillated by an air or steam cylinder C through a link 18 and a lever 22. The levers 74, 78 are connected to a lever 23 rigidly fixed to the shaft 21 by latches 24, as shown in Fig. 8, so that any set of clinkerbreakers may be put into operation.