BRAKE MECHANISM FOR DIFFERENTIAL VEHICLE LOADINGS

• US 3,612,230 A
• Filed: 01/07/1970
• Issued: 10/12/1971
• Est. Priority Date: 01/07/1970
• Status: Expired due to Term

• Current Assignee: Robert L. Ludington, Robert M. Holloway
• Original Assignee: Robert L. Ludington, Robert M. Holloway
• Inventors: Ludington, Robert L., Holloway, Robert M.
• Primary Examiner(s): Reger, Duane A.
• Application Number:
  US05/001,266
• Time in Patent Office: 643 Days
• Field of Search: 188/153,195,198-203 303/22,23
• US Class Current: 188/195
• CPC Class Codes: B60T 8/1812 characterised by the means for pressure reduction
• CPC Class Codes: B60T 8/185 Arrangements for detecting vehicle level
• CPC Class Codes: B60T 8/1893 especially adapted for railway vehicles

Abstract

A fluid cylinder and piston and piston sleeve arrangement for providing different brake pressures with different vehicle loads in which the piston sleeve is limited in its movement by means controlled in accordance with the spacing between a pair of members of the vehicle, the spacing being determined by the vehicle load.

Claims

1. Braking apparatus for a railway car having a stationary truck side frame, a truck bolster mounted for vertical movement, the vertical position being responsive to the load carried by said railway car, said apparatus comprising control means actuatably responsive to the relative positions of said truck side frame and said truck bolster, a fluid cylinder, an outer piston sleeve mounted in said fluid cylinder, an inner piston mounted in said outer piston sleeve, a push rod carried by said inner piston, a return spring for said outer piston sleeve and said inner piston, means for limiting the outer piston sleeve'"'"''"'"'s operative travel with respect to the inner piston'"'"''"'"'s operative travel only when said brake mechanism is applied and said railway car is in a nonloaded condition, said means for limiting the outer piston sleeve'"'"''"'"'s operative travel being movable by said control means, whereby said push rod transmits a first force when said railway car is empty and a second force when said railway car is loaded, lever means, said lever means being actuated by said push rod and a brakeshoe mechanism, said lever means being connected to said brakeshoe mechanism.

2. Braking apparatus for a railway car having a stationary truck side frame, a truck bolster mounted for vertical movement, the vertical position being responsive to the load carried by said railway car, said apparatus comprising a fluid cylinder, an outer piston sleeve mounted in said fluid cylinder, an inner piston mounted in said outer piston sleeve, a push rod carried by said inner piston, a sleeve carried by said inner piston and said push rod being mounted in said sleeve and being free to float when a handbrake is applied, a return spring for said outer piston sleeve and said inner piston, means for limiting the outer piston sleeve'"'"''"'"'s operative travel with respect to the inner piston'"'"''"'"'s operative travel only when said brake mechanism is applied and said railway car is in a nonloaded condition, whereby said push rod transmits a first force when said railway car is empty and a second force when said railway car is loaded, lever means, said lever means being actuated by said push rod and a brakeshoe mechanism, said lever means being connected to said brakeshoe mechanism.

3. Braking apparatus for a railway car having a stationary truck side frame, a truck bolster mounted for vertical movement, the vertical position being responsive to the load carried by said railway car, said apparatus comprising a fluid cylinder, an outer piston sleeve mounted in said fluid cylinder, an inner piston mounted in said outer piston sleeve, a push rod carried by said inner piston, a return spring for said outer piston sleeve and said inner piston, means for limiting the outer piston sleeve'"'"''"'"'s operative travel with respect to the inner piston'"'"''"'"'s operative travel only when said brake mechanism is applied and said railway car is in a nonloaded condition, whereby said push rod transmits a first force when said railway car is empty and a second force when said railway car is loaded, lever means, said lever means being actuated by said push rod and a brakeshoe mechanism, said lever means being connected to said brakeshoe mechanism, and at least one additional intermediate piston sleeve mounted between said outer piston sleeve and said inner piston, and means for limiting the intermediate piston sleeve'"'"''"'"'s operative travel with respect to the inner piston'"'"''"'"'s operative travel when said brake apparatus is applied and said railway car is in a partially loaded condition whereby said push rod transmits a first force when said railway car is empty, a second force when said railway car is partially loaded and a third force when said railway car is in a loaded condition.

4. Braking apparatus for a railway car having a stationary truck side frame, a truck bolster mounted for vertical movement, the vertical position being responsive to the load carried by said railway car, said apparatus comprising a fluid cylinder, an outer piston sleeve mounted in said fluid cylinder, an inner piston mounted in said outer piston sleeve, a push rod carried by said inner piston, a return spring for said outer piston sleeve and said inner piston, means for limiting the outer piston sleeve'"'"''"'"'s operative travel with respect to the inner piston'"'"''"'"'s operative travel only when said brake mechanism is applied and said railway car is in a nonloaded condition, said means for limiting the outer piston sleeve'"'"''"'"'s operative travel with respect to the inner piston'"'"''"'"'s operative travel only when said brake apparatus is applied and said railway car is in an empty condition comprising a stop pin mounted for projection through said fluid cylinder to engage the end of said outer piston sleeve, means for retracting said stop pin when said railway car is in a loaded condition, whereby said push rod transmits a first force when said railway car is empty and a second force when said railway car is loaded, lever means, said lever means being actuated by said push rod and a brakeshoe mechanism, said lever means being connected to said brakeshoe mechanism.

5. Apparatus according to claim 3, wherein said means for limiting the outer piston sleeve'"'"''"'"'s operative travel and the means for limiting the intermediate piston sleeve'"'"''"'"'s travel comprises a stop pin mounted for protrusion through said fluid cylinder to engage the end of said outer piston sleeve and the end of said intermediate piston sleeve, means for retracting said pin a first distance to allow movement of said intermediate piston'"'"''"'"'s sleeve but preventing movement of said outer piston sleeve when said railway car is in a partially loaded condition, and for retracting said pin a second distance to allow movement of said intermediate piston sleeve and said outer piston sleeve when said railway car is in a loaded condition.

6. Apparatus according to claim 5 wherein said stop pin protrudes through said fluid cylinder in a nonpressure area of the cylinder.

7. Apparatus according to claim 4 wherein said means for retracting said stop pin comprises a cable having one end attached to said pin, means attached to the other end of said cable operatively responsive to the vertical position of said bolster.

8. Braking apparatus for a railway car having a stationary truck side frame, a truck bolster mounted for vertical movement, the vertical position being responsive to the load carried by said railway car, said apparatus comprising a fluid cylinder, an outer piston sleeve mounted in said fluid cylinder, an inner piston mounted in said outer piston sleeve, a push rod carried by said inner piston, a return spring for said outer piston sleeve and said inner piston, means for limiting the outer piston sleeve'"'"''"'"'s operative travel with respect to the inner piston'"'"''"'"'s operative travel only when said brake mechanism is applied and said railway car is in a nonloaded condition, said means for limiting the outer piston sleeve'"'"''"'"'s operative travel with respect to the inner piston'"'"''"'"'s operative travel only when said brake apparatus is applied and said railway car is in an empty condition comprising a stop pin, an opening in said fluid cylinder through which said pin is projectable, a stop pin housing mounted on the outside of said fluid cylinder in which said stop pin is mounted, a stop pin spacEr fixedly mounted on said pin, a stop pin return spring interposed between said housing and said spacer to urge said pin to project through said opening and engage the end of said outer piston sleeve, cable means having one end attached to said pin for retracting said pin, said cable means passing through said housing, and means attached to the other end of said cable means operatively responsive to the vertical position of said truck bolster, whereby said push rod transmits a first force when said railway car is empty and a second force when said railway car is loaded, lever means, said lever means being actuated by said push rod and a brakeshoe mechanism, said lever means being connected to said brakeshoe mechanism.

9. Apparatus according to claim 8 further comprising a fluid in said housing, and wherein said stop pin spacer has a substantially close sliding fit within said stop pin housing and wherein said stop pin spacer has holes therethrough for the passage of said fluid.

10. Apparatus according to claim 8 further comprising spring means interposed in said cable means.

11. Apparatus according to claim 8 further comprising a fluid in said housing, and wherein said stop pin spacer has holes for the passage of said fluid therethrough, a spring mounted in said cable means.

12. Apparatus according to claim 8 wherein said cable means comprises a cable mounted in a sheath, one end of said cable being attached to the stop pin and the adjacent end of said sheath being attached to the stop pin housing, a bracket mounting on said truck side frame, the other end of said cable being attached to said bracket, the other end of said cable sheath being attached to said truck bolster in a position adjacent said bracket whereby vertical movement of said truck bolster with respect to said truck side frame causes responsive movement of said stop pin.

13. Apparatus according to claim 12 further comprising a lock block for attaching the other end of said cable to the bracket, and further comprising a cable guide mounted on said truck bolster, a locking cap mounted on said cable guide and a seal mounted on said locking cap, said cable sheath being attached to said cable guide and said cable extending upwardly through said cable guide and said locking cap and said seal.

14. Apparatus according to claim 7 wherein said means attached to the other end of said cable operatively responsive to the vertical position of said truck bolster, comprises a lever having one end pivotally connected to said truck bolster, a medial portion of said lever being connected to said truck side frame, said cable having one end connected to the other end of said lever, the distance between the truck bolster connection and the truck side frame connection being less than the distance between the truck side frame connection and the cable connection on said lever arm, whereby movement of said cable with respect to said sheath is greater than the movement of said truck bolster with respect to the truck side frame.

15. Braking apparatus for a railroad car having a stationary truck side frame, a truck bolster mounted for vertical movement, the vertical position being responsive to the load carried by said railway car, said apparatus comprising a fluid cylinder, an outer piston sleeve mounted in said fluid cylinder, an inner piston mounted in said outer piston sleeve, a push rod carried by said inner piston, a return spring for said outer piston sleeve and said inner piston, a stop pin, an opening in said fluid cylinder through which said pin is projectable, a stop pin housing mounted on the outside of said cylinder in which said stop pin is mounted, a stop pin spacer fixedly mounted on said stop pin, a stop pin return spring interposed between said housing and said spacer to urge said pin to project through said opening and engage the end of said outer piston sleeve, a cable mounted in a sheath, one end of said cable being attached to said stop pin and the adjacent end of said sheath being attachEd to the stop pin housing, a bracket mounted on said truck side frame, the other end of said cable being attached to said bracket, the other end of said cable sheath being attached to said truck bolster in a position adjacent said bracket, whereby vertical movement of said truck bolster with respect to said truck side frame causes responsive movement of said stop pin.

16. Braking apparatus for a vehicle having load responsive means and brake means for retarding movement of said vehicle, said apparatus comprising control means actuatably responsive to said load responsive means, a fluid cylinder, a piston sleeve mounted for movement in said cylinder, a piston mounted in said cylinder for movement with and for movement separately from said sleeve, means for urging said piston and said sleeve into a predetermined brake release position in said cylinder, means for supplying fluid under pressure to said cylinder to move said sleeve and said piston from said release position to second positions, means for interconnecting said piston and said brake means, and means for limiting the movement of said sleeve away from said release position under control of said load responsive means, said means for limiting the movement of said sleeve being movable by said control means.

17. Braking apparatus for a vehicle having load responsive means and brake means for retarding movement of said vehicle, said apparatus comprising a fluid cylinder, a piston sleeve mounted for movement in said cylinder, a piston mounted in said cylinder for movement with and for movement separately from said sleeve, means for urging said piston and said sleeve into a predetermined brake release position in said cylinder, means for supplying fluid under pressure to said cylinder to move said sleeve and said piston from said release position to second positions, means for interconnecting said piston and said brake means, and means for limiting the movement of said sleeve away from said release position under control of said load responsive means, said load responsive means comprising a pair of spaced members, the spacing of which being determined by the load on said vehicle and said means controlled by said load responsive means comprising means insertable into and out of the path of movement of said sleeve.

18. Apparatus as set forth in claim 16 wherein said sleeve extends around said piston and has a substantially fluidtight but separable connection therewith in said release position.

19. Braking apparatus comprising a fluid cylinder, an outer piston sleeve mounted in said fluid cylinder, an inner piston mounted in said outer piston sleeve, a push rod carried by said inner piston, a stop pin mounted for projection through said fluid cylinder to engage the end of said outer piston sleeve to transmit a first braking force, means for retracting said stop pin to transmit a second braking force.

20. Braking apparatus comprising a fluid cylinder, an outer piston sleeve mounted in said fluid cylinder, an intermediate piston sleeve mounted in said outer piston sleeve, an inner piston mounted in said intermediate piston sleeve, a push rod carried by said inner piston, a stop pin mounted for projection through said fluid cylinder to engage the end of said outer piston sleeve and the end of said intermediate piston sleeve, means for retracting said pin a first distance to allow movement of said intermediate piston sleeve but preventing movement of said outer piston sleeve, and for retracting said pin a second distance to allow movement of said intermediate piston sleeve and said outer piston sleeve.

21. Apparatus according to claim 19 further comprising a stop pin housing mounted on the outside of said fluid cylinder in which said stop pin is mounted, a stop pin spacer fixedly mounted on said pin, a stop pin return spring interposed between said housing and said spacer to urge said pin to project through said opening and engage the end of said outer piston sleeve, a cable having one end attached To said pin for retracting said pin, said cable passing through said housing.

22. Braking apparatus for a railway car having a stationary truck side frame, a truck bolster mounted for vertical movement, the vertical position being responsive to the load carried by said railway car, said apparatus comprising a fulcrum lever having one end pivotally anchored to said car body, motive means connected to an intermediate portion of said fulcrum lever, said motive means comprising a fluid cylinder, an outer piston sleeve mounted in said fluid cylinder, an inner piston mounted in said outer piston sleeve, a push rod carried by said inner piston, a return spring for said outer piston sleeve and said inner piston, means for limiting the outer piston sleeve'"'"''"'"'s operative travel with respect to the inner piston'"'"''"'"'s operative travel only when said brake apparatus is applied and said railway car is in an empty condition, whereby said push rod transmits a first force when said railway car is empty and a second greater force when said railway car is loaded, a first pull rod having one end connected to the other end of said fulcrum lever, a live lever, the other end of said first pull rod connected to one end of said live lever, a second pull rod, the other end of said live lever being connected to one end of said second pull rod, a first brakeshoe mechanism, the other end of said second pull rod being connected to said first brakeshoe mechanism, slack adjusting means having one end connected to an intermediate portion of said live lever, a center rod having one end connected to the other end of said slack adjusting means, a dead fulcrum lever having one end pivotally anchored to said car body, the other end of said center rod being connected to a medial portion of said dead fulcrum lever, a third pull rod having one end connected to the other end of said dead fulcrum lever, a second brakeshoe mechanism, the other end of said third pull rod being connected to said second brakeshoe mechanism, said slack adjusting means being extensible and retractable for eliminating the slack and controlling the travel of said brakeshoe mechanisms, said slack adjusting means being lockable in a rigid condition when transmitting the braking force to said brakeshoe mechanisms.

23. Braking apparatus for a railway car having a stationary truck side frame, a truck bolster mounted for vertical movement, the vertical position being responsive to the load carried by said railway car, said apparatus comprising a live lever, motive means connected to one end of said live lever, said motive means comprising a fluid cylinder, an outer piston sleeve mounted in said fluid cylinder, an inner piston mounted in said outer piston sleeve, a push rod carried by said inner piston, a return spring for said outer piston sleeve and said inner piston, means for limiting the outer piston sleeve'"'"''"'"'s operative travel with respect to the inner piston'"'"''"'"'s operative travel only when said brake apparatus is applied and said railway car is in an empty condition, whereby said push rod transmits a first force when said rail car is empty and a second force when said rail car is loaded, a first pull rod having one end connected to the other end of said live lever, a first brakeshoe mechanism, the other end of said first pull rod being connected to said first brakeshoe mechanism, slack adjusting means having one end connected to an intermediate portion of said live lever, a center rod having one end connected to the other end of said slack adjusting means, a dead fulcrum lever having one end pivotally anchored to the car body, the other end of said center rod being connected to a medial portion of said dead fulcrum lever, a second pull rod having one end connected to the other end of said dead fulcrum lever, a second brakeshoe mechanism, the other end of said second pull rod being connected to said second brakeshoe mechanism, said slack adjusting means being extensible and retractable for eliminating the slack and controlling the trAvel of said brakeshoe mechanisms, said slack adjusting means being lockable in a rigid condition when transmitting the braking force to said brakeshoe mechanisms.

24. Braking apparatus for a railway car having a stationary truck side frame, a truck bolster mounted for vertical movement, the vertical position being responsive to the load carried by said railway car, said apparatus comprising a first lever having one end pivotally mounted on said bolster, a fluid piston and cylinder assembly including a fluid cylinder, an outer piston sleeve mounted in said fluid cylinder, an inner piston mounted in said outer position sleeve, a push rod carried by said inner piston, said push rod being connected to the other end of said first lever, a return spring for said outer piston sleeve and said inner piston, means for limiting the outer piston sleeve'"'"''"'"'s operative travel with respect to the inner piston'"'"''"'"'s operative travel only when said brake apparatus is applied and said railway car is in an empty condition, whereby said push rod transmits a second greater force when said railway car is loaded, a truck live lever slidably engageable with a medial portion of said first lever, a first brakeshoe mechanism connected to a medial portion of said truck live lever, a slack adjuster having one end thereof connected to the other end of said truck live lever, a truck dead lever having one end thereof connected to the other end of said slack adjuster, a dead lever having both ends attached to said bolster, the other end of said truck dead lever being slidably engageable with a medial portion of said dead lever, a second brakeshoe mechanism connected to a medial portion of said truck dead lever, said slack adjusting means being extensible and retractable for eliminating the slack and controlling the travel of the brakeshoe mechanisms, said slack adjusting means being lockable in a rigid condition when transmitting the braking force to the brakeshoe mechanisms.