Cross blending electro-dynamic/friction brake system for multi-car train consist having mixed power and non-power cars
First Claim
1. A cross-blending brake system for a train of cars including at least one power car having electro-dynamic brake means therefor and at least one non-power car comprising:
- (a) a brake pipe extending continuously through said train of cars in which fluid under pressure is carried;
(b) a signal wire extending continuously through said train of cars in which an electrical current is carried;
(c) a brake valve device including a control handle rotatable in a brake application range between full release and full service brake positions to effect a corresponding variation in the level of said brake pipe fluid pressure and said signal wire current, said brake pipe fluid pressure providing an analog fluid pressure brake demand signal, and said signal wire current providing an analog electric brake demand signal to control said electro-dynamic brake means in accordance with the desired rate of train retardation;
(d) means for providing a feedback signal corresponding to the regenerative current of said electro-dynamic brake means;
(e) means for providing a first control signal, the value of which is the same as the value of said electric brake demand signal when said feedback signal corresponds to said electric brake demand signal and is less than the value of said electric brake demand signal by an amount proportional to the difference between said electric brake demand signal and said feedback signal when said electric brake demand signal exceeds said feedback signal;
(f) a fluid-pressure-operated brake unit on said at least one power car and on said at least one non-power car;
(g) first blending valve means including first and second motor means subject respectively to said fluid brake demand signal and to said first control signal for producing a differential force in response to which said non-power car brake unit is operated to provide friction braking thereat when said differential force occurs as a result of the force exerted by said first motor means being greater than the force exerted by said second motor means;
(h) means for amplifying said feedback signal to provide a second control signal; and
(i) second blending valve means including third and fourth motor means subject respectively to said fluid pressure brake demand signal, and to said second control signal for producing a differential force in response to which said power car brake unit is operated to provide friction braking thereat when said differential force occurs as a result of the force exerted by said third motor means being greater than the force exerted by said fourth motor means.
5 Assignments
0 Petitions
Accused Products
Abstract
A cross blending brake system for a multi-car train having power cars that provide regenerative braking through the electro-dynamic action of the car'"'"'s traction motors, as well as friction braking through an electric/friction brake blending valve, and non-power cars that provide friction braking only through an electric/friction brake blending valve. Since the regenerative brake effort on the power cars is limited only by the available wheel to rail adhesion on these cars, the regenerative action of the electro-dynamic brake provides brake effort in excess of the power car brake requirement, thus reducing the friction brake requirement of the non-power cars, which is limited by the lower threshold energy absorption ability of the wheels. The cross blending control utilizes the excess power car regenerative braking to avoid overheated wheels, while at the same time realizing a net energy savings and reduced brake shoe wear, particularly at maximum levels of regeneration.
43 Citations
13 Claims
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1. A cross-blending brake system for a train of cars including at least one power car having electro-dynamic brake means therefor and at least one non-power car comprising:
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(a) a brake pipe extending continuously through said train of cars in which fluid under pressure is carried; (b) a signal wire extending continuously through said train of cars in which an electrical current is carried; (c) a brake valve device including a control handle rotatable in a brake application range between full release and full service brake positions to effect a corresponding variation in the level of said brake pipe fluid pressure and said signal wire current, said brake pipe fluid pressure providing an analog fluid pressure brake demand signal, and said signal wire current providing an analog electric brake demand signal to control said electro-dynamic brake means in accordance with the desired rate of train retardation; (d) means for providing a feedback signal corresponding to the regenerative current of said electro-dynamic brake means; (e) means for providing a first control signal, the value of which is the same as the value of said electric brake demand signal when said feedback signal corresponds to said electric brake demand signal and is less than the value of said electric brake demand signal by an amount proportional to the difference between said electric brake demand signal and said feedback signal when said electric brake demand signal exceeds said feedback signal; (f) a fluid-pressure-operated brake unit on said at least one power car and on said at least one non-power car; (g) first blending valve means including first and second motor means subject respectively to said fluid brake demand signal and to said first control signal for producing a differential force in response to which said non-power car brake unit is operated to provide friction braking thereat when said differential force occurs as a result of the force exerted by said first motor means being greater than the force exerted by said second motor means; (h) means for amplifying said feedback signal to provide a second control signal; and (i) second blending valve means including third and fourth motor means subject respectively to said fluid pressure brake demand signal, and to said second control signal for producing a differential force in response to which said power car brake unit is operated to provide friction braking thereat when said differential force occurs as a result of the force exerted by said third motor means being greater than the force exerted by said fourth motor means. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
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Specification