GB1029496A - Improvements in and relating to turbochargers - Google Patents

Abstract

1,029,496. External band brakes; external shoe-drum brakes. SCHWITZER CORPORATION. March 19, 1964, No. 11573/64. Heading F2E. [Also in Division F1] An I.C. engine turbo charger has braking means including a braking shoe 54, Fig. 7, normally biased against its shaft so as to prevent rotation, the shaft being released when a predetermined pressure of the shaft lubricant is present in the braking means. When shaft 57 is stopped and there is no lubricant pressure in its bearings, spring 51 acts through piston 52, spacer 62 and the toggle linkage 58, 59 to force the shoe 54 against shaft 57. After starting the lubricant flows through spaces between block 56 and bore 47 and increasing lubricant pressure overcomes spring 51, thus causing piston 52 to move towards cap 49. A leaf spring 69 lightly biases spacer 62 towards surface 53, thus allowing shoe 54 to move away from shaft 57 which can then rotate. In another embodiment a piston 17, Fig. 2 (not shown), which is corrected through a projection 21a to a rotatable sleeve 28 secured to one end of a helical band 32 which is anchored at its other end to a fixed sleeve, is acted on by a spring 24 so that band 32 prevents rotation of shaft 31 when there is insufficient lubricant pressure in chamber 18. A force multiplying linkage may be interposed between piston 17 and stem 21.