Brakes – Elements – Shoe fasteners
Reexamination Certificate
1999-12-22
2001-10-16
Oberleitner, Robert J. (Department: 3613)
Brakes
Elements
Shoe fasteners
C188S247000, C188S242000
Reexamination Certificate
active
06302247
ABSTRACT:
FIELD OF THE INVENTION
This invention relates, in general, to brake shoes and brakeheads for railway vehicles; i.e., railway cars, transit cars and locomotives. More particularly, this invention relates to a new and unique backing plate and brakehead system for railway brake shoes having improved mounting features for assembling such brake shoe on the brakehead without the use of keys or screws.
BACKGROUND OF THE INVENTION
Railway brake shoes are typically mounted on brake rigging of railway vehicles by means of a brake shoe key, which passes through a longitudinal slot in the brake shoe holder or “brakehead” of the brake rigging and concurrently through mounting holes of the brake shoe backing plate. Such holes are normally located in a central “keybridge” area of the brake shoe backing plate. The keybridge area of the backing plate is generally formed in such a way that it is adapted to protrude into or intersect with a longitudinal slot in the brakehead at or near the center of the brakehead's length.
A certain type of railroad transit vehicle utilizes brake shoes made of a solid processed wooden material and having a different mounting system. Such shoes are mounted to the brakehead by means of brass screws which project through the face of the brakehead and are embedded into the body of the brake shoe. Wooden shoes have been used on these vehicles because, heretofore, other types of composition brake shoes have caused excessive brake squeal when the brake was applied to the wheels of these vehicles. The noise tendency is related to the unique shape of the wheel and the suspension of the wheel, which is used primarily for the braking function and does not normally contact a rail surface during operation. The wooden type of brake shoe has been found most resistant to noise generation, and the existing mounting arrangement has been reliable for the wooden type of brake shoe, although it has several disadvantages. These include a time consuming assembly process which requires the use of power tools and reduction in useable thickness of the brake shoe in order to avoid contact between the screw and the wheel as the brake shoe wears.
While new composition materials have been developed which have acceptable noise characteristics, these types of material have mechanical properties different than wood, such that the screw mounting system is not as reliable as when used with wooden brake shoes. It also has been recognized that the depth of the screws require the brake shoe to be replaced while there is still significant thickness of material on the brake shoe, which could otherwise contribute to a longer useable life of the brake shoe. Therefore, an alternate design of the mounting system was desired.
SUMMARY OF THE INVENTION
The present invention provides a brake shoe mounting system for railway vehicles. This system includes a composition type brake shoe having a recessed center portion and two bracket-style backing plates integrally molded into the composition type brake shoe. There is one bracket style backing plate per each half of the brake shoe. Each bracket style backing plate further includes at least two projections extending outwardly from a convex surface of the composition type brake shoe. At least one projection extending outwardly is closely adjacent a first end of the composition brake shoe and at least one projection extending outwardly from the convex surface of the composition type brake shoe is closely adjacent the recessed center portion of the composition type brake shoe. The mounting system provided by the present invention further includes a modification to the brakehead having a concave surface with a central projection for engaging the recessed center portion of the convex surface of the brake shoe. The brakehead modification is comprised of a first recessed area closely adjacent a first end of the brakehead for receiving projections extending outwardly from the backing plate and a second recessed area closely adjacent the central projection for receiving the at least one projection extending outwardly from the backing plate. The mounting system also includes a securing means for securing the backing plate that is integrally molded to the brake shoe to the brakehead.
OBJECTS OF THE INVENTION
Accordingly, it is a primary object of this invention to provide a new and improved brake shoe for railway vehicles having improved means for mounting the brake shoe on the brakehead.
Another primary object of this invention is to provide a new and improved backing plate for brake shoes on railway vehicles having improved means for properly assembling the brake shoe on the brakehead.
Another object of the present invention is to provide a mounting system which will permit increased usable thickness of the brake shoe compared to the presently used screw type mounting system.
It is still another object of the present invention to design a specially configured spring retainer to secure the brake shoe to the brakehead.
Yet another object of the invention is to integrally mold a bracket-style backing plate into the body of the brake shoe.
Still another object of this invention is to provide a new and unique system for assembling such brake shoe to the brakehead.
An even further object of this invention is to provide a unique mounting system which would allow continued and interchangeable use of the present wooden brake shoe type without modification.
These and other objects and advantages of this invention will become apparent after a full reading of the following detailed description, particularly, when read in conjunction with the attached drawings as described below and the appended claims.
REFERENCES:
patent: 785303 (1905-03-01), Gallagher
patent: 785355 (1905-03-01), Gallagher
patent: 817541 (1906-04-01), Armbrust
patent: 1892816 (1933-01-01), Thornburgh
patent: 2266984 (1941-12-01), Moore
patent: 3235952 (1966-02-01), Arrasmith
patent: 4000792 (1977-01-01), Guldin
patent: 5275263 (1994-01-01), Mezger
patent: 5407031 (1995-04-01), Christie
patent: 5429215 (1995-07-01), King
patent: 5890566 (1999-04-01), Yoshida et al.
patent: 0071762 (1982-05-01), None
patent: 2087995 (1982-06-01), None
patent: 57177437 (1982-11-01), None
Kahr Joseph C.
McCabe Thomas W.
James Ray & Associates
Nguyen Xuan Lan
Oberleitner Robert J.
Westinghouse Air Brake Company
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