Empty load device

• US 6,666,528 B1
• Filed: 08/28/2002
• Issued: 12/23/2003
• Est. Priority Date: 08/28/2002
• Status: Active Grant

• Current Assignee: New York Air Brake Corporation (Knorr-Bremse GmbH)
• Original Assignee: New York Air Brake Corporation (Knorr-Bremse GmbH)
• Inventors: Spadaccini, Michael, Gayfer, Robert
• Primary Examiner(s): Schwartz, Christopher P.
• Application Number:
  US10/228,987
• Time in Patent Office: 482 Days
• Field of Search: 303/9.69, 303/22.1, 303/22.2, 303/22.7, 303/22.8
• US Class Current: 303/9.69
• CPC Class Codes: B60T 8/1818 Lever mechanism
• CPC Class Codes: B60T 8/1893 especially adapted for railway vehicles

Abstract

An empty-load system including a first housing having brake cylinder, control valve, equalization volume reservoir and pilot ports. The first housing also has a ratio means for controlling the connection between ports and has a piston responsive to a pilot pressure to operate the ratio means. The system also includes a second housing having a brake cylinder port and a pilot port connected, respectively, to the brake cylinder port and the pilot port of the first housing. The second housing also has a sensor means, having a sensor piston, for sensing the load of a railcar and has a sensor valve for connecting the brake cylinder port to the pilot port for a first position of the sensor piston.

Claims

1. An empty-load system comprising:

a first housing having brake cylinder, control valve, equalization volume reservoir and pilot ports;

ratio means, in the first housing and having a ratio piston and a ratio valve, for controlling the connection of the control valve port to the brake cylinder port and to the equalization port;

a pilot piston in the first housing being responsive to a pilot pressure at the pilot port to operate the ratio valve;

a second housing having a brake cylinder port and a pilot port connected respectively to the brake cylinder port and the pilot port of the first housing;

a sensor means, in the second housing and having a sensor piston, for sensing a load of a railroad car; and

a sensor valve, in the second housing and connected to the sensor piston, connects the brake cylinder port to the pilot port for a first position of the sensor piston.

2. The system of claim 1, wherein the pilot piston includes a rod for operating the ratio valve;

and including a guide in the first housing separating the pilot piston from the ratio mean, and the rod extends through the guide.

3. The system of claim 2, wherein the guide is configured to open the ratio valve for a first position of the ratio piston.

4. The system of claim 3, wherein for a first pilot pressure, the rod is retracted into the guide.

5. The system of claim 2, wherein for a first pilot pressure, the rod is retracted into the guide.

6. The system of claim 1, including a spring in the first housing biasing the pilot piston to open the ratio valve;

and a first pilot pressure, above a value which will counteract the pressure of the spring, allows closing of the ratio valve.

7. The system of claim 1, wherein the sensor valve is a spool valve in a bore in the second housing;

a pair of o-rings on the spool define a chamber in the bore;

a passage in the spool valve connects two areas in the bore on opposite ends of the chamber;

the brake cylinder port, the pilot port and a vent port are connected to the bore such that the chamber connects the pilot port and the vent port for a first position of the spool valve; and

the passage connects the pilot port and the brake cylinder port for a second position of the spool valve.

8. The system of claim 7, wherein only one of the o-rings traverses one of the port connections between the first and second positions.

9. The system of claim 1, wherein the sensor valve is a spool valve connected to a diaphragm sensor piston by a lost motion connection.

10. The system of claim 1, wherein the volume of the connection of the two pilot ports is less than 100 cubic inches.