초록 ▼

A high capacity, multiple-stage railway car switching yard connects together two or more subyards. Each subyard has a fully open arrival/departure end and may have a continuously descending gradient throughout the entire length of its classification tracks. The subyards are positioned opposite one a

A high capacity, multiple-stage railway car switching yard connects together two or more subyards. Each subyard has a fully open arrival/departure end and may have a continuously descending gradient throughout the entire length of its classification tracks. The subyards are positioned opposite one another, so classification tracks of one subyard can serve as receiving tracks for another subyard. Escape tracks are interconnected between the two subyards to provide a higher capacity and more efficiency and flexibility than a single yard by itself.

대표청구항 ▼

A high capacity, multiple-stage railway car switching yard connects together two or more subyards. Each subyard has a fully open arrival/departure end and may have a continuously descending gradient throughout the entire length of its classification tracks. The subyards are positioned opposite one a

A high capacity, multiple-stage railway car switching yard connects together two or more subyards. Each subyard has a fully open arrival/departure end and may have a continuously descending gradient throughout the entire length of its classification tracks. The subyards are positioned opposite one another, so classification tracks of one subyard can serve as receiving tracks for another subyard. Escape tracks are interconnected between the two subyards to provide a higher capacity and more efficiency and flexibility than a single yard by itself. The apparatus of claim 1 further comprising an air flow switch upstream from the first diverter valve, and a pilot air flow path pneumatically connecting the air flow switch to the first diverter valve and to the second diverter valve; wherein upon receipt of a pneumatic signal indicating activation of said tool, the air flow switch pressurizes the pilot air path and the pressurized pilot air flow path actuates the first and second diverter valves to direct the flow of said compressed air through the first air flow path; and wherein upon receipt of a pneumatic signal indicating deactivation of said tool, the air flow switch vents and thus depressurizes the pilot air flow path thereby actuating the first and second diverter valves to direct the compressed air through the second air flow path. 3. The apparatus according to claim 1, wherein the air flow controller comprises an air chamber, the diaphragm dividing the air chamber into a first subchamber and a second subchamber, the first air portal tube pneumatically connecting the first point in the fixed orifice obstruction to the first subchamber, and the second air portal tube pneumatically connecting the second point in the fixed orifice obstruction to the second subchamber. 4. The apparatus according to claim 3, wherein the spring biased needle in the air flow controller is normally biased in the fully open position, and wherein deflection of the diaphragm is proportional to the pressure differential between the first and second points in the fixed orifice obstruction. 5. The apparatus according to claim 4, the air flow controller further comprising a manual adjustment knob including a counteracting spring, said counteracting spring being biased in direction urging the needle toward a closed position. 6. A method for controlling the flow rate of compressed air delivered to a tool, the method comprising: receiving compressed air from an air pressurizing source; directing the compressed air through a flow path including fixed orifice obstruction thereby producing a pressure differential between a first point and a second point in said flow path; reproducing substantially the same pressure differential within an air flow control chamber located adjacent to said fixed orifice obstruction; and in response to said pressure differential, sliding a needle into said fixed orifice obstruction to thereby partially restrict the flow rate of the compressed air through the flow path. 7. The method of claim 6, further comprising: biasing said needle so that the fixed orifice obstruction is normally fully open, and sliding said needle to restrict the flow rate by deflecting a diaphragm, said diaphragm being connected to said needle, said diaphragm and needle being contained within said air flow control chamber. 8. The method of claim 7, wherein said diaphragm essentially divides said air flow control chamber into a first subchamber and a second subchamber, and the method further comprises producing a pressure differential between the first subchamber and second subchamber to thereby deflect the diaphragm. 9. The method of claim 8, further comprising: biasing said needle with a spring force; and balance the pressure differential between the first and second subchambers with the spring force. 10. The method of claim 9, further comprising adjusting a counteracting spring biased in a direction opposite said spring force. 11. An apparatus for controlling the flow rate of compressed air to a tool, said tool being optimally operative dependant upon receiving a specified flow rate of said compressed air, said apparatus comprising: an air inlet for receiving compressed air from an air pressurizing source; an air outlet for transmitting the compressed air to the tool; a first air flow path between the air inlet and the air outlet; a second air flow path between the air inlet and the air outlet; said first air flow path further comprising: an air flow control meter, s