Abstract: Fluid flow in a conduit is measured by placing a flow block in the conduit which introduces variations in the flowpath which cause local pressure variations. The pressure variations are converted to electrical signals by transducers, and the electrical signals are processed to obtain flow rate values. To provide a correction for transducer drift, the transducer signals are examined during a time when there is known to be zero flow in the conduit. The difference between the transducer signals during a time when there is zero flow is used as a measure of transducer drift. A value for the drift is stored in computer memory and used subsequently, when fluid flow is resumed. This invention is specifically intended for use in railroad airbrake systems, where it is used in a locomotive to provide an accurate and reliable measurement of air supplied to the brake pipe of the air brake system.

Abstract: Apparatus for interlocking independent control handles for throttle action, dynamic brake action and reverser action, within a control stand for a railway locomotive to permit controlled removal of a reverser control handle in which a first and second cam disks are mounted to a first and second axle for rotation with a throttle handle and a dynamic brake handle such that the disks will interlock with each other so that neither the throttle or dynamic handle can be rotated unless the other is in an "off" position, and having a pivotal lock member secured to the reverser axle, with a member thereon adapted to pivotally lock the reverser lever handle in place when it is secured to the reverser axle.

Abstract: A locomotive throttle controller having a CPU and output driver stage. Such CPU generates an analog voltage based on software logic and transmits to the output driver stage a signal indicative such analog voltage. Such output driver stage receives the signal from such CPU and uses it to provide an analog output voltage signal to a trainline which monitors and/or controls dynamic braking. The improvement therewith of an apparatus, for feeding back from such output driver stage to the CPU an analog signal indicating status of such trainline, comprising a device for obtaining a first analog voltage signal from a node which supplies current to such trainline. A voltage-divider for dividing the first analog voltage signal into a lower range to obtain a second analog voltage signal. A signal generating device connected to receive the second analog voltage signal and generate a third analog voltage signal.

Abstract: Apparatus for determining and encoding the position of a reverser control handle on a control stand of a locomotive or other railway transit vehicle of the type having a reverser control handle attached to an axle partially rotatable through a defined angle and including a pair of stationary signal transmitting sensor means, and a pair of sensor activators secured to the axle adapted for partial rotation with the axle, whereby one each of the pair of sensor activators are positioned proximate to one each of the signal transmitting sensor means, so that any partial rotation of the axle in one given will be sensed by one such signal transmitting sensor means to provide a second signal, and partial rotation of the axle in the opposite direction will be sensed by the other signal transmitting sensor means to provide a second signal.

Abstract: An automatic slot identification and address decoding arrangement having a motherboard for conveying address information, data and control signals to printed circuit cards. An electrical cable connector for establishing a particular address for each of the printed circuit cards. Each of the printed circuit cards includes a programmable logic device for dynamically recognizing the address information received from the motherboard, and each of the printed circuit boards includes electronic circuitry for conveying the data and control signals to the electrical cable connector.

Abstract: An H-5 relay air valve emulating circuit for use in an electropneumatic railway brake control equipment including an operational amplifier comparator and a solenoid relay. The operational amplifier comparator includes a positive and a negative input and an output. The positive input is connected to an automatic brake cylinder request terminal, while the negative input is connected to a reference signal terminal. The output of the operational amplifier comparator is connected to the electrical coil of the solenoid relay which has a movable heel contact as well as a front and a back contact. The front contact is connected to an independent brake cylinder request terminal, while the back contact is connected to a zero reference terminal. The movable heel contact of the solenoid relay is connected to an independent contact point of a J-relay emulating circuit which is conditioned to either produce 160% of the simulated control pressure signal or to produce 100% of the simulated control pressure signal.

Abstract: An electronic sanding control system for enhancing the frictional adhesion existing between the track rail and the wheels of a railway vehicle by functionally controlling the energization and deenergization of a sanding magnet valve with a plurality of OR and AND logic gates and a sand control latch circuit.

Abstract: A recoverable bail-off circuit and a direct release and non-recoverable bail-off circuit for enhancing the bail-off function of the air brake pressure on a railway locomotive including a first logic circuit for ascertaining when a non-recoverable bail-off command is present by determining the presence of a manual bail-off signal or the presence of a dynamic bail-off signal and by determining the absence of an emergency brake signal, an electronic and logic circuit for ascertaining when a direct release command is present by determining a freight/passenger mode signal and that a present brake pipe pressure signal is greater than a previous brake pipe pressure signal by a certain pressure and a second logic circuit for ascertaining when a recoverable bail-off command is present by determining the presence of the manual bail-off signal or the presence of a dynamic bail-off signal and determining the presence of the emergency brake signal.

Abstract: An arrangement for enhancing a bail-off function a railway vehicle comprising, a non-recoverable bail-off circuit for supplying an output signal to a brake cylinder calculation circuit when a bail-off condition a freight operating mode, a drop in brake pipe pressure is present, and an emergency brake state is absent, a recoverable bail-off circuit for supplying an output signal to the brake cylinder calculation circuit when a bail-off condition and an emergency brake state is present, the brake cylinder calculation circuit supplying an automatic brake cylinder demand signal on one input of a relay valve emulation circuit and receiving an independent brake cylinder demand signal on another input of, the relay valve emulation circuit which supplies output signal to a feedback control circuit producing output signals which are supplied to an application valve and a release valve for controlling the level of air pressure in an air brake cylinder, and a transducer for sensing and feeding back a signal correspondin

Abstract: An electropneumatic locomotive brake system including an emulation routine for electronically simulating the functional operations of a relay air valve and for producing electrical output signals, an application electromagnetic and a release electromagnet receiving the electrical output signals and pneumatically controlling a J-relay air valve, a source of compressed air connected to the J-relay air valve and the application electromagnet and an air brake cylinder connected to the J-relay air valve for establishing the level of compressed air in the air brake cylinder in accordance with an automatic brake request and an independent brake request received from a brake command controller located in the cab of the locomotive.