US738833A

US738833A - Car-brake.

Info

Publication number: US738833A
Application number: US13075402A
Authority: US
Inventors: Thomas E Mccollum
Original assignee: Individual
Current assignee: Individual
Priority date: 1902-11-10
Filing date: 1902-11-10
Publication date: 1903-09-15
Anticipated expiration: 1920-09-15

Description

No. 738,833. PATENTED SEPT. 15, 1903. T. E. MoUOLI-UM.

GAR BRAKE.

APPLIOATIOH FILED NOV. 10, 1902.

H0 MODEL.

' HHHH.

@gmv

[fa crab)" UNITED STATES Patented September 15, 1903.

THOMAS E. MCOOLLUM, OF TORONTO, CANADA.

CAR-BRAKE.

SPECIFICATION forming part of Letters Patent No. 738,833, dated September 15, 1903.

Application filed November 10,1902. Serial No. 130,754. (No model.)

To all whom it may concern:

Be it known that I, THOMAS E. MoOoLLUM, electrician, of the city of Toronto, county of York, Province of Ontario, Canada, have invented certain new and useful Improvements in Oar-Brakes, of which the following is a specification.

My invention relates particularly to that class of brakes known as momentumbrakes, in which the momentum of the car is relied on to provide the necessary power to apply the brakes. In these brakes a chain is wound on a drum carried by one of the axles to apply the brake. If, then, after the car has been stopped on a grade the brake be released, the car will roll back, and the brake cannot be reapplied until the chain has been unrolled from the drum and rewound the reverse way. This back roll? is likely to occur when the motorman after a stop on a grade has released the brake in response to a signal to go ahead and then immediately gets a signal to stop. The current being off and the brake released, the car rolls back, as described; and it is the object of my present invention to remove this objection to momentum-brakes by providing means operated from the same brake-staff as the momentumbrake for catching and holding the car on grades whenever back roll is imminent.

With this object in view my invention consists, essentially, in connecting two chains to the brake-staff, one adapted to be wound up by the rotation of the staff in one direction, the other by its rotation in the opposite direction, one chain being connected with the momentum-brake-operating mechanism, substantially as hereinafter more specifically described and then definitely claimed.

Figure 1 is a skeleton plan showing the arrangement of brake mechanism provided with my improvements. Fig. 2 is a perspective detail showing the method of connecting the operating-chains to the brakestaff. Fig. 3 is a similar view showing a modification of these connections. Fig. 4 is a side elevation of the momentum-brake and its operating connections. Fig. 5 is a sectional elevation showing means for adjusting and holding the brakestaff. Fig. 6 is a plan view of the same parts.

In the drawings like letters of reference indicate corresponding parts in the difierent figures.

In Fig. 1 I show the wheels of a car-truck and the ordinary brake mechanism, comprising the brake-beams A and the connecting and supporting frame B. The brakes are applied through the medium of the lovers 0, pivotally connected,respectively, with the brakebeams and the frame 13 by means of the links D and E. Two of these levers may be employed, as shown in the drawings, or in some cases only one is used, depending entirely upon the arrangements provided for operating the brake mechanism. My improvements are eqnallyapplioable in either case. On one of the axles is secured a momentum-brake F. This brake may be of any form, though I illustrate a brake such as described and shown in my prior United States patent, No. 684,581, issued on the 15th day of October, 1901. I might, however, use a momentum-brake such as shown in my United States Patent No. 709,923, issued on the 30th day of September, 1902, or any other form of brake in which power other than manual is employed for the purpose of applying the brakes. The brake shown, it will be seen, is operated by the connecting-rod G, operating the system of levers H, by means of which the wedge-Wheels I, described in the first United States patent referred to, are caused to operate the momentum-brake. To the end of this rod is connected a chain J, the other end of which is wound partly around and secured to the small drum K, secured to the brake-stafi L. A chain M is secured at one end to one of the levers O and has its other end secured to the end of the finger N, secured to the brakestaff, as shown particularly in Fig. 2. In this chain a certain amount of slack is left when the brake-shoes are out of contact with the wheels, as shown in Fig. l. The purpose of the finger N is to rapidly take up the slack in the chain when the brake-staff is revolved to tighten this chain. As, however, the presence of the finger is sometimes considered a disadvantage as requiring more power to be applied to the brake-staif by.the operator to apply the brakes by hand, I illustrate in Fig.

3 a direct connection to the brake-staif. The construction there shown will answer the purpose of my invention.

The operation of the device is substantially as follows: Under normal conditions the parts occupy substantially the position shown in Fig. 1, the precise angle of the crank-handle 0 being of course immaterial. Presuming the motorman to be called on to stop, he will swing the crank-handle in the direction indicated by arrow. This Will wind the chain Jupon the drum K, causing the wedge-wheels I to apply the momentum-brake. The rotation of the momentum-brake winds the chain P on the drum of the brake, and the lefthand brake-lever C is operated through the medium of the connectingrod Q. The brakeshoesare thus applied to the wheels. If this stop has been made on a grade and the crankhandle 0 be moved back to release the momentum-brake, the car will start to roll back. If the motorman desires to hold the car, he has merely to move the crank-handle in the reverse direction to that indicated by arrow, when the chain M is wound on the brakestaff and the brake -shoes applied to the wheels through the medium of the right-hand lever 0. Of course, if so desired, the chain M might be run straight through to the left-.

hand lever O. The slack in the chain M prevents the brake-lever, to which it is connected, being operated when the crank-handle is being rotated to apply the momentum-brake. Oon versely, when the handle is being rotated to cause the chain M to operate the brakelever, to which it is connected, the chain J unwinds from the drum, so that the momentum-brake-controlling mechanism is not in anywise affected. I prefer that when the brake-handle is in its normal position the turn of chain shown should be wrapped on the drum, as the momentum-brake, which is that ordinarily employed, is thus operated at once by the movement of the brake-handle without the necessity of taking up any slack.

As it may frequently be desirable to hold the brake-staff as set to apply the brakes either directly or indirectly, I connect with the brakestaif two ratchet-wheels R and S, with their teeth set in opposite directions. On the carplatform is pivoted a dog T, having one end adapted to engage the lower ratchet-wheel S and its other end bent up to engage the upper ratchetwheel R. It follows that the dog may be used to hold the brake-staff after it has 1 been rotated in either direction.

is wound the chain M. Between the ratchetwheels R and S, I form a ratchet-clutch V, with its teeth oppositely set to the teeth of the rachet-wheel S. If it be found that in directly applying the brakes the handle gets into an awkward position at such time as the brake-shoes are in contact with the wheels and the advantageous application of power is essential, the sleeve U may be held by the dog T and the brake-handle rotated back to a better position. As the brake-staff is free to move vertically in its bearings, it lifts to allow the ratchet-clutch V to slip backward and take a grip in the new position. At any time the sleeve may be allowed to take up its normal position by lifting the brake-stafi to release the clutch V, when the tension of the chain M will rotate the sleeve to the desired point.

The adjusting means for the brake-staff just described are valuable, as it isimpossible to keep brake mechanism in such shape that the brake-handle can be depended upon to be in a good position for the motorman to apply his strength in the most advantageous manner at the proper time. As the power required to apply the momentum-brake is much less than that required to apply the brakes directly,the position of-the handle during application is not very important.

What I claim as my invention is-- 1. Ina car-brake, brake mechanism; power mechanism for operating the brake mechanism; and controlling means for the power mechanism, in combination with a chain adapted to operate the power-controlling means to apply the brakes; a chain directly connected to the brake mechanism and adapted to operate the same; and a brake-staff to which both the chains are connected so that one chain is drawn upon by turning the staff in one direction and the other chain by turning the stafi in the reverse direction, substantially as described.

2. In a car-brake, brake mechanism; power mechanism for operating the brake mechanism; and controlling means for the power mechanism, in combination with a chain adapted to operate the power-controlling means to apply the brakes; a chain directly connected to the brake mechanism; a brake- :staif to which the direct brake-operatin g chain is directly connected; and a small drum secured to the staff around which the other chain is partly wound and to which its end is con nected, these connections being so made that one chain is drawn upon by turning the stafi in one direction, and the other chain by turn ing the staff inv the reverse direction, substantially as described.

- 3. In a car-brake, brake mechanism; power mechanism for operating the brake mechanism; and controlling means for the power mechanism, in combination with a chain adapted to operate the power-controlling means to apply the brakes; achain directly connected to the brake mechanism; a brakestaff to which the direct brake-operating chain is directly connected, with a little slack; and

a small drum secured to the staff around which the other chain is partly wound and to which its end is connected, these connections being so made that one chain is drawn upon by turning the staff in one direction, and the other chain by turning the staff in the reverse direction, substantially as described.

4. In acar-brake, brake mechanism; power mechanism for operating the brake mechanism; and controlling means for the power mechanism, in combination with a chain adapted to operate the power controlling means to apply the brakes; a chain directly connected to the brake mechanism; a brakestaff; a finger connected to the brake-staff to the end of which the end of the direct brakeoperating chain is connected with a little slack; and a small drum secured to the staff around which the other chain is partly wound and to which its end is connected, substantially as described.

5. In a car-brake, brake mechanism; power mechanism for operating the brake mechanism; and controlling means for the power mechanism, in combination with a chain adapted to operate the powercontrolling means to apply the brakes; a chain directly connected to the brake mechanism and adapted to operate the same; abrake-staff to which both 'the chains are connected so that one chain is drawn upon by turning the staff in one direction and the other chain by turning the staffin the reverse direction; two ratchetwheels secured to the brake-staff and having their teeth set in opposite directions; and a double dog suitably pivoted and adapted to engage one ratchet-wheel with one end and the other with its other end, substantially as described.

6. In acar-brake, brake mechanism; power mechanism for operating the brake mechanism; and controlling means for the power mechanism, in combination with 'a chain adapted to operate the power controlling means; a chain directly connected to the brake mechanism and adapted to operate the same; a vertically-movable brake-stafi to which the first chain is connected; a sleeve loose on the stalf and to which the second chain is connected; a ratchet-wheel secured to the said sleeve and suitably supported; a-

dog adapted to engage the said ratchet-wheel; a wheel fast on the brake-staif above the ratchet-wheel; and a ratchet-clutch formed between the two wheels with its teeth oppositely set to the teeth of the ratchet-wheel, substantially as described.

7. Inacar-brake, brake mechanism; power mechanism for operating the brake mechanism; and controlling means for the power mechanism, in combination with a chain adapted to operate the powercontrolling means; a chain directly connected to the brake mechanism and adapted to operate the same; a vertically movable brake staff to which the first chain is connected; a sleeve loose on the staff and to which the second chain is connected; a ratchet-wheel secured to the said sleeve and suitably supported; a second ratchet-wheel fast on the brake-staff above the first ratchet-wheel; a ratchet-clutch formed between the two wheels with its teeth oppositely set to the teeth of the first ratchetwheel; and a dog adapted to engage either ratchet-wheel, substantially as described.

8. In a car-brake the combination of a vertically-movable brake-staff; a sleeve loose on the shaft; a brake-operating chain fast to the sleeve; a ratchet-wheel secured to the said sleeve and suitably supported; a dog adapted to engage the said ratchet-wheel; a wheel fast on the brake-staff above the ratchetwheel; and a ratchet-clutch formed between two wheels with its teeth oppositely set to the teeth of the ratchet-wheel, substantially as described.

Toronto, October 29 1902.

. THOMAS E. IVIOCOLLUM.

In presence of-- J. EDW. MAYBEE, A. J. OoLBoURNn.