US336117A - Safety device for inclined railways - Google Patents

Description

(NoModeL) 2 Sheets-Sheet 1. G. W. JESSOP.

SAFETY DEVICE FOR INCLINED RAILWAYS.

Patented Feb. 16, 1886.

N. PETER5. Fholn-Lhhcgmphur. Washington. 0. c.

(No Model.) 2 Sheets-Sheet 2. G. W. J ESSOP.

SAFETY DEVICE FOR INGLINED RAILWAYS.

Patented Feb. 16

iil/

UNITED STATES PATENT OFFICE.

GEORGE NV. JESSOP, OF PITTSBURG, PENNSYLVANIA.

SAFETY DEVICE FOR INCLINED RAILWAYS.

SPESIFICATION forming part of Letters Patent No. 336,117, dated February 16, 1886.

Application filed June 22, 1885. Serial No. 169,365. (No model.)

To all whom it may concern.-

Be it known that I, GEORGE W. JEssoP, of Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Safety Devices for Inclined Railways; and I do hereby declare the following to be a full, clear, and exact description thereof.

The object of my invention is to provide means for preventing those accidents on inclined railways which result from the breaking of the traction-cables.

It consists in the automatic device for checking the car immediately upon its breaking loose, hereinafter set forth and claimed.

I will describe my improvement with reference to the accompanying drawings, in which Figure lis a plan view of the device applied to a car-truck. Fig. 2 is a side view of the same. Fig. 3'is a transverse section on the line y y of Fig. 1, Fig. 2 being shown partly in section on the line was of Fig. 1.

Like letters of reference indicate like parts wherever they occur.

In the drawings,2 represents the outer frame of a railway-car truck for use on inclined planes, and 3 and 4 the wheels,which are fixed on each side of the car to rotary axles 5 and 6; and 7 are the rails upon which the ear travels. The safety clamps or brakes used in checking the car upon the occurrence of an accident consist of grippingjaws 8, pivoted together at 9, and provided with upwardly extending arms or levers 10 and 11. (See Fig. 3.) The jaws 8 are situate so as to inelose the rail, leaving a sufficient space between the jaws and the web, that the car may move freely on the track without interfering with it. A transverse rotatory shaft, 12, is journaled parallel with and just back of one of the axles, 5, and passes through the jawlevers, or through boxes 25, affixed thereto, the part which traverses one of the arms, 11, or its box being provided with a left-hand thread, and the part which traverses the other arm, 10, or its box being screw-threaded in the opposite direction, the holes in the arms themselves or in their boxes 25 being correspondingly threaded, so that as the shaft is turned in one direction it may bring thegripping-jaws 8 together to clamp the inclosed rail, and if it be reversed the jaws may be spread apart again.

The shaft 12 is journaled'in housings 13 on the sides of the truck-frame, and is provided with a spur-wheel, 14, whose periphery is situate opposite to the periphery of a similar spur-wheel, 15, affixed to the axle 5. mally, these spurwheels are kept separate and out of gear, so that while 15 rotates coutinuously with the axle, as the car moves on its track, the spur-wheel 14 and the shaft 12 are ordinarily at rest. set in motion by engagement of the rotating spur-wheel 15 with its companion wheel 14, the revolution of the shaft will act upon the threaded lever'arms and if the car be moving If, however, they be down the plane will bring the ends of the gripping-jaws together to clamp the web of the rail very firmly. The friction thus caused will stop the car almost immediately. This operation is performed automatically by the following arrangement of mechanism: The

housings of the transverse shaft 12 are slotted lengthwise of the car, as shown at 16 in Fig. 2, so that the shaft may be movable throughout the length of the slots, toward or away from the axle 5. A spring, 17, is affixed at one end to a block or box, 18, on the shaft 12, and at the other end to a similar box on the axle 5, or to another convenient point of at tachment, the tensile strain of the spring being such as to tend to draw the shaft 12 in its slotted bearings toward the axle and to bring the spur- wheels 14 and 15 into gear. They are, however, kept out of gear by the traction-cable 19, which is secured to one end of a lever, 20, pivoted to a beam or brace, 21, of the truck-frame. The other end of the lever 20 is attached to the shaft 12 by a connectingbar, 22, the parts being relatively so arranged that the strain of traction upon the lever 20 may act upon the shaft 12 to overcome the power of the spring 17, and to pull the shaft away from the axle, thereby disengaging the spur- wheels 14 and 15. The weight of the car, relatively to the tension of the spring should besufficientto overcome the latter, and when the car is dependent upon the cable, to keep the shaft 12 far enough from the axle to prevent meshing of their spurwheels.

I have described only one clamp or brake and one set of gear-wheels for operating them. In practice I prefer, however, to have at least four of these brakes and two of the shafts 12, one of the latter placed adjacent to each caraxle, and a'clamp arranged on the ends of each shaft, there being thus two for each rail of the track. The corresponding lever-arms of the gripping-levers on each side of the car are preferably connected by braces 23, which serve to hold them steadily in place. Each of the shafts 12 is journaled in elongated bearings, as before described, and is provided with one'or more retracting-levers, 20, to keep the spurwheels 14 out of gear with their pinions 15. I have shown four of these levers-two for each axle-the levers on each side of the car being attached to a separate traction-cable.

Thus constructed, the operation of my improved device is as follows: So long as the cables remain intact, and the weight of the car is upon them, the shaft 12 will be out of gear and the clamping or braking jaws unaffected. If, however, the cables should break,the weight of the car being immediately released from the levers 20, the springs 17 will draw the shafts 12 toward the rear and front axles, respectively, thereby bringing the several sets of spurwheels 14 and 15 into gear. The motion of the car as it descends the inclined plane will turn the axles 5 and 6, and, acting on the screwthreaded shafts 12, will bring the jaws of the clamps together upon the rails, and will stop the car in a short time. It is of course desirable that the rails should be very firmly secured to their bed, so that the sudden stopping of the car may not tear them up. For this purpose I prefer to bolt the rails to their ties rather than to spikethem, as now usually done. The rails may also be arranged without fishplates or splice-bars, which might catch upon the several jaws are clamped, thus adding to the strength and speed of action of the device. The gripping-jaws need not act upon the rails of the car-track, but may be arranged to inclose a separate rail or rails bolted to the ties between or outside of the track-rails, or they may act upon a rod or cable unbolted to the ties, but coextensive with the track, and secured at the upper terminus thereof. I do not, therefore, desire to limit myself to the precise arrangement of mechanism herein shown and described, nor do I desire to limit its use to inclined planes, since it may be applied to elevators or other lifting devices; but

WVhat I claim as my invention, and desire to protect by Letters Patent, is

1. The combination, in a lift-car, of a rod extending longitudinally with the car-track, a clamp for engaging the rod, a rotatory shaft connected with the clamp and threaded so as to cause the same to be clamped by rotation of.

the shaft, gearing for connecting the car-axle with said shaft, the latter being connected with being movable toward each other, a spring for so moving the same, and a tractioncable connected with the shaft and capable of keeping the same out of gear from the aXle by its tension, substantially as described.

In testimony whereof I have hereunto set my hand this 16th day of June, A. D. 1885.

GEORGE W. JESSOP.

Witnesses:

W. B. Conwm, T. W. BAKEWELL.

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