. Railway and locomotive engineering : a practical journal of railway motive power and rolling stock . may thus be August, iqo4. RAILWAY AND LOCOMOTIVE ENGINEERING 353 occupied by the dull in travcrsiiiR thedistance, up wliich it can be drawn ina fraction of a second. The mechanical time lock is securelyfastened in a case, and though it hasni> external or entertaining feature likethe doll, it nevertheless depends uponthe time a vertical bar takes to descendwhen hampere<I in its fall by a vibratingmechanism, and the bar, like the danc-ing doll, can be raised to the desiredIicight in the f
. Railway and locomotive engineering : a practical journal of railway motive power and rolling stock . may thus be August, iqo4. RAILWAY AND LOCOMOTIVE ENGINEERING 353 occupied by the dull in travcrsiiiR thedistance, up wliich it can be drawn ina fraction of a second. The mechanical time lock is securelyfastened in a case, and though it hasni> external or entertaining feature likethe doll, it nevertheless depends uponthe time a vertical bar takes to descendwhen hampere<I in its fall by a vibratingmechanism, and the bar, like the danc-ing doll, can be raised to the desiredIicight in the fraction of a second. In our illustration, Fig. 3, A is a ver-tical rack bar engaging with the similarteeth of a ratchet wheel B. The longteeth of the ratchet wheel engage witha pawl attached to the gear C, and theteeth of this wheel gear with a pinionD which has a small clock work es-capement wheel keyed on the sameshaft. The escapement and pendulumare easily discernible in the figure, inwhich the pendulum is marked F. Inthe back of the upright bar A, nearthe top, is a notch in which lies a small. DERAILINtt SWITCH ON A TROLLEY LINEAT A RAILROAD CROSSING. roller wheel at the end of a lockingbar E. As A rises the locking bar ismoved to the left and remains in thatposition until notch and roller againcoincide, when A has run down to itsoriginal position. The movement of the lever of thehome signal raises the bar A up to thedesired height and it does so in thetime occupied in clearing the raising of A pushes the lockingbar E to the left and the lever cannotnow be returned to its former positionuntil the bar A has dropped once A has been raised the pawlcarried the wheel C around and causesthe pendulum to vibrate, and the es-capement to step oft a long series ofconsecutive short drops and halts, forthe vertical bar A. As much as aminute, if necessary, may be occupiedin letting A sink down to the unlockingposition, from which it may have beenraised in something
Size: 1567px × 1595px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, bookidrailwaylocom, bookyear1901
