MXPA99011315A - Locomotive to ecp brake conversion system - Google Patents

Abstract

A conversion system enables a locomotive equipped with a conventional pneumatic brake control system to control braking on a train whose railcars each have electrically controlled pneumatic (ECP) brake equipment. The conversion system includes a power conversion mechanism, a signal conversion mechanism and two pressure reduction circuits. The power conversion mechanism converts battery voltage received from a power trainline of the locomotive to a predetermined nominal voltage. Made available to an ECP trainline that runs along the railcars, the predetermined nominal voltage is used to power the ECP brake equipment on each railcar in the train. The signal conversion mechanism converts the pneumatic brake commands carried in the brake pipe of the locomotive into electrical brake commands corresponding thereto. Transmitted along the ECP trainline, the electrical brake commands control the ECP brake equipment on each railcar and the braking effort deliverable thereby. Part of the signal conversion mechanism, the first pressure reduction circuit is used to reduce the railcar brake pipe pressure to an emergency level when the brake pipe in the locomotive carries a pneumatic emergency brake command. The first pressure reduction circuit then pneumatically commands the ECP brake equipment to make an emergency brake application. The second pressure reduction circuit assures that the railcar brake pipe pressure reduces to the emergency level when the locomotive brake pipe pressure drops below a prespecified level.

Description

ECP BRAKE CONVERSION SYSTEM FOR LOCOMOTIVES FIELD OF THE INVENTION The invention relates to two basic types of brake control systems, both well known and widely used in the railway industry: (1) the conventional brake control system by means of the which a locomotive is capable of controlling the brakes in wagons equipped with pneumatic brake equipment; and (2) a brake control system based on the ECP through which a locomotive is able to control the brakes in wagons equipped with pneumatic brake equipment (ECP) electrically controlled. More particularly, the invention pertains to a system that allows a locomotive equipped with the conventional brake control system to control the brakes on wagons equipped with the innovative electrically controlled pneumatic brake equipment (ECP). BACKGROUND OF THE INVENTION The following background information is provided to assist the reader in understanding the invention described and claimed below. In accordance with the foregoing, none of the terms used herein is proposed to be limited to any particular narrow interpretation unless specifically stated otherwise in this document. For a train headed by a locomotive equipped with the conventional brake control system, a pneumatic train line known as the "brake pipe" is the only means by which emergency and service brake commands are transmitted to each one of the wagons on the train. The brake pipe is essentially a continuous long pipe that extends from the main locomotive to the last car on the train. The brake pipe is currently composed of a series of sections of interconnected pipe, with a section of pipe secured to the bottom of each car. The brake pipe is formed by connecting each section of pipe through a coupler to another section of pipe in an adjacent car. As seen in Figure 1, it is to this brake pipe 1 that the pneumatic brake equipment is connected in each car through a branched pipe 2. The pneumatic brake equipment in each car includes two storage tanks 3 and 4, one or more brake cylinders 5 and at least one pneumatic brake control valve 6 such as a valve type ADB, ABDX or ABDW made by Westinghouse Air Brake Company (WABCO). Under conditions known in the art of brake control, the pneumatic brake control valve 6 charges the two tanks 3 and 4 with the pressurized air that it receives from the brake pipe 1. It is the pressure level inside the pipe of the brake. brake 1 which determines whether the brake control valve 6 will certainly load these tanks or supply pressurized air previously stored in one or both of these tanks towards the brake cylinders 5. When they are pressurized, the brake cylinders 5 convert the pressurized air that they receive from the brake control valve 6 to mechanical force. From the brake cylinders this force is transmitted through the mechanical link to the brake shoes. The magnitude of the braking force applied to the wheels is directly proportional to the pressure formed in the brake cylinders. Forced against the wheels of the truck and / or the disc brakes, the brake shoes are used to decrease or stop the rotation of the wheels. For trains equipped with the conventional brake control system, it is therefore the level of pressure in the brake pipe 1 that determines whether and to what extent the car brakes will be applied. In addition to the brake pipe, the locomotive has its own pneumatic train lines that include a main tank compensation pipe (MRE), an independent release and application pipe (IAR) and a drive pipe. Within a composition of locomotives (ie, two or more locomotives connected together), the drive, IAR and MRE pipes of each locomotive are connected to the drive, IAR and MRE pipes of the adjacent locomotives. The MRE pipe is used to charge the brake pipe to a normal operating pressure of approximately 90 psi when the brakes are released. Incidentally, it is the pressure within the IAR pipe that controls the supply of pressurized air to and consequently the operation of the brakes of the locomotive (s) on the train. The locomotive also features a multi-cable electric train line known as the multi-unit (MU) line cable. The MU line cable consists of twenty-seven (27) different electrical lines. As it is well known in the railway industry, the MU line cable contains an alarm line in which the locomotive equipment can transmit various signals to alert the train operator about the critical conditions that occur in the locomotive. The MU line cable also contains 74V DC power lines and return lines in which the battery power from the locomotive is supplied to the various energy consumption devices in the train. There are many different types of conventional brake control systems in use in the railroad industry. An example of a conventional type of brake control system is the Air Brake Control System of the 26-L locomotive manufactured by WABCO. A conventional brake control system, such as System 26-L, has two brake handles referred to as automatic and independent brake handles. By placing these handles in the proper positions, a train operator in the locomotive can control how to operate the brakes on the locomotive (s) and wagons. More specifically, by moving these handles to the proper position, the train operator can control how much pressure will develop in the IAR and brake lines, as well as in the other pneumatic train lines of the train. It is by such a control of the pressure level in the brake pipe 1, for example, that the pneumatic brake equipment in each car is controlled. By moving the independent brake handle, the train operator can steer the conventional system only to apply or release the brakes on the locomotive (s). In contrast, by moving the automatic brake handle, the operator can direct the brake control system to apply or release the brakes both on the locomotive (s) and on the wagons on the train. The level at which the system decreases or increases the pressure within the brake pipe 1 and consequently the amount of braking energy exerted by the train brakes, corresponds finally to the position of the automatic brake handle. The automatic brake handle can be moved from and between a release position at one end (where the brake pipe pressure is maximum and the brakes are fully released) to an emergency position at the other end (where the pressure of brake pipe is zero and the brakes are fully applied).

The positions for the automatic brake handle include release, minimum service, full service, suppression, continuous and emergency service. Between the minimum and full service positions is the service area where each increasing movement of the automatic brake handle to the full service position results in an increasing decrease in brake pipe pressure. The exact amount by which the brake pipe pressure is decreased depends on how far the brake handle moves to the full service position. It is this decrease in pressure that signals the pneumatic brake control valve (s) 6 in each car to supply pressurized air from one or both tanks to the brake cylinders to apply the car brakes. The amount of pressure formed in the brake cylinders and consequently the magnitude of the braking force applied to the wheels, is proportional to the amount to which the pressure of the brake pipe has been lowered. When the automatic brake handle moves from within the service area or above to the release position, the manner in which the brakes operate depends on whether the brake equipment is designed to allow a gradual release of the brakes . Passenger trains typically have brake equipment that allows a gradual release of the brakes when the brake control system of the locomotive is set to the "passenger service" mode of operation. The brake train of the freight train, in contrast, typically allows only a direct release of the brakes. For the direct release equipment, in response to such movement of the automatic brake handle, the brake control system does not command an increase in pressure within the brake pipe 1 until the automatic brake handle is placed in the position of liberation. Once the pressure in the brake pipe rises above a pre-set level (eg, 2 psi), the control system and the affected brake brake control valves respond by fully venting the brake cylinders completely releasing so the brakes of the train. For the graduated release equipment, in response to such movement of the automatic brake handle to the release position, the brake control system orders an increase in the pressure in the brake pipe increasingly. The level at which the brake pipe pressure increases depends on the degree to which the automatic brake handle moves to the release position. Unlike the brake control system of the locomotive and the pneumatic brake control valves to direct the release equipment, those designed for the release of graduated brake react to this increasing increase in the pressure of the brake pipe when reducing proportionally the pressure in the brake cylinders thus decreasing the force with which the brakes of the train are applied. For a train headed by a locomotive equipped with the innovative brake control system based on ECP, the brake commands are transmitted primarily to each of the wagons electrically via a line of the two-wire ECP train. Specifically, both service and emergency brake commands are electrically communicated through this line of the ECP train to the ECP brake equipment in each wagon in the train. The ECP brake equipment in each car is basically the same as the pneumatic brake equipment previously described, except for the pneumatic brake control valve 6. As is well known in the art, a wagon control unit (CCU) is used. ), one or more pressure transducers and various pneumatic and electro-pneumatic valves instead of the pneumatic brake control valve. The pressure transducers are used to monitor the pressure inside the brake pipe and brake cylinders as well as the pressure inside the tanks. Similar to the branch pipe 2 shown in figure 1, the branch wiring is used to connect the CCU to the ECP train line. Supplied from the 74V DC power line of the locomotive's MU line cable, the ECP train line operates at a nominal 230V cc to turn on the ECP brake equipment in each car. For wagons equipped with ECP brake equipment, the brake pipe 1 still serves as the source of pressurized air from which tanks 3 and 4 are loaded in each wagon. During service and emergency braking, it is still from one and both tanks, respectively, that the pressurized air is supplied to the brake cylinders 5 to apply the car brakes. However, in -the ECP brake control system, the brake pipe is not used to transmit the service brake commands. It is used only to transmit emergency brake commands as a pneumatic backup for the electric emergency brake commands transmitted along the ECP train line. If the ECP brake equipment loses power or otherwise fails electrically, it will generally respond pneumatically to an emergency pressure decrease in the brake pipe by supplying pressurized air from both tanks to the brake cylinders thus causing an application of emergency of the car brakes. The brake control system based on the ECP in the locomotive includes a cabin station unit and a master controller from which the brakes on the train are finally controlled. The inputs of the handle (s) or buttons are processed by the cabin unit and then passed to the main controller. Operate in accordance with the instructions contained within its programming code, in response to these and other inputs, the main controller formulates an appropriate brake command for the current conditions and transmits it along the ECP train line to each of them. the vehicles on the train. The brake order and other ECP messages are transmitted through the ECP train line through a power line communications system such as the Echelon LonWorks System specified by the American Association of Railroads (AAR). )). The master controller can order through the brake command any action from a brake release to an emergency brake application or any degree of brake application between those two extremes. The brake equipment can also be designed to provide graduated release of the brakes. The degree of brake application ordered by the main controller is typically transmitted in terms of a percentage of the pressure required for the full service brake application. Zero percent (0%) is typically designed for a brake release, 15% for a minimum service brake application, 100% for a full service brake application and 120% for an emergency brake application. Each CCU includes a transceiver device and a microprocessor unit. Controlled by the microprocessor unit, the transceiver is connected through the branch wiring to the ECP train line from which it receives the electric brake commands issued by the main controller. The transceiver converts the electric brake order into a form usable by the microprocessor. In a manner well known in the brake control technique, the microprocessor controls the previously mentioned electro-pneumatic valves through which the pressurized air can be supplied or emptied from the brake cylinders 5 in the car in accordance with the dictates of the invention. particular electric brake order received. The communications network on board an ECP-based train typically consists of the main controller and the power line communication system in the main locomotive and the CCU on board each wagon as well as the ECP train line through the who communicate. The main controller is responsible for most of the communication via the ECP train line that transmits the most recently formulated brake order to all wagons on the train. The main controller also regroups the wagons at a predetermined speed (for example, every second) . Each CCU has its own unique identification code that transmits to the locomotive when it is regrouped and reports information about its operations to the main controller. Specifically, sequentially or according to other criteria, the master controller supplies a status request directed to a wagon to determine if the selected CCU is attentive to the brake control system. When requested, a selected CCU will respond normally to the interrogation unless it has lost the ability to communicate which in turn provides an indication of its status to the main controller. Taking the form of identification code, the response to the request also typically includes other ECP operational data such as brake pipe pressure, brake cylinder pressure, battery voltage, reservoir pressure (s) and if the brakes on the wagon or one of its trucks are included (enabled) or interrupted (disabled). By its response, the selected CCU informs the main controller that it is a part that properly operates the ECP brake control system. Apart from the regrouping cycle, a CCU can send an alarm message on its own initiative. Each wagon through its CCU can consequently report critical data and other diagnostic information to the main controller if any of the following conditions occur: improper brake cylinder pressure, failure of a cargo tank to charge, abnormally low pressure in the cargo pipe, brake or in one of the tanks or fails to receive communications. The CCU can also issue specific control messages in response to other diverse circumstances as is well known in the brake control technique. Many trains, equipped with either ECP or conventional brake control systems, are also equipped with any of several radio end-of-train telemetry systems (EOT) known. These systems typically include a locomotive control unit (LCU) located in the locomotive and a subsequent unit EOT installed in the last car on the train. The EOT unit is coupled to the brake pipe in the last car by means of a hose and a glad hand coupling.

In a one-way EOT system, the EOT unit transmits, via radio signals to the LCU, data pertaining to the pressure in the brake pipe and the movement of the last car. To do this, the EOT unit includes a pressure transducer to monitor the pressure of the brake pipe, a motion detector to detect the movement of the car, a microprocessor unit to control the overall operation of these components and a transmitter that the unit microprocessor used to transmit this data from the last car. In the locomotive, the LCU includes a primary deployment display screen, a receiver to receive transmissions from the EOT unit and a microprocessor unit. Controlled by the microprocessor unit, the display screen is used to transmit the data from the last car to the train operator. In addition, in response to an emergency order transmitted through the EOT unit, the LCU will also display that there is an emergency condition in the back of the train. The EOT unit is typically configured so that the emergency condition represents a sudden loss of brake pipe pressure or a drop in brake pipe pressure below a predetermined level. For a train equipped with a one-way EOT system, the application of the emergency brake starts at the locomotive and progresses along the brake pipe to the last car. For long trains, reducing the pressure in the brake pipe from the train head can be time-consuming, particularly for a train equipped with a conventional pneumatic brake control system. In addition, if one of the angle locks is left closed or the brake pipe is restricted, the brake equipment beyond the restriction may not receive the emergency brake command necessary to apply the brakes in an emergency. For this reason, two-way EOT systems have been developed under the auspices of the AAR. In a two-way EOT system such as the EOT TRAINLINK® II system manufactured by WABCO, the LCU and the EOT unit still perform all functions attributed to their counterparts in the one-way EOT system. The EOT unit is therefore still used to transmit the aforementioned radio signals by which the brake pipe pressure of the last car and the movement data are transmitted to the LCU. However, the two-way EOT and LCU units are each equipped with a transceiver (i.e., transmitter and receiver in combination) as compared to the single transmitter and receiver for the one-way EOT and LCU units, respectively. The EOT unit also has an emergency brake valve that is controlled by its microprocessor unit and the LCU also includes an emergency lever switch. When changing this switch to an emergency, the train operator may cause the LCU to transmit an emergency brake radio signal to the EOT unit. Through its microprocessor unit, the EOT unit responds to this emergency signal by ordering its emergency brake valve to decrease the pressure of the brake pipe at an emergency speed. Combined with the emergency decrease in brake line pressure activated from the main end of the train using the aforementioned brake systems, the EOT two-way system allows even faster application of the car brakes in an emergency . In this two-way EOT system, the LCU has a primary display screen panel that features a dedicated display screen for each of the various data types of the last car. The data of the last wagon deployed include the pressure of the brake pipe, condition of the low battery, if the car stops or is in motion and if an emergency has been enabled or disabled. The LCU also has a supplementary message display screen by which it visually transmits additional information such as, for example, data related to the erection of the EOT system and whether the EOT and LCU unit communicate properly or not. For a train equipped with a conventional pneumatic brake control system inside the brake pipe is used to pneumatically transmit both service and emergency orders to the wagons, another EOT radio telemetry system can be used, such as the TRAINLINK system ® IS manufactured by WABCO. Of course, it is well known that an emergency application starts at a much faster speed than a service application. Typically, the decrease in emergency pressure propagates along the brake pipe at a speed of approximately 900 feet / sec. Consequently, for a train of one mile in length, the propagation time would be in the range of 10 to 15 seconds. In contrast, a service application can take more than a minute to reach the last car; therefore, the need for and development of the TRAINLINK® system. In addition to the two-way LCU and EOT units, the TRAINLINK® ES system has a Service Interface Unit (SIU) that connects between the serial port of the LCU ES and the brake pipe in the locomotive. The SIU provides the LCU ES with the pressure of the current brake pipe. This allows the LCU ES to automatically start a service brake application in the last car simultaneously with the service decrease in the pressure of the brake pipe activated from the locomotive. Specifically, the LCU in the locomotive automatically transmits a service brake radio signal to the EOT ES unit when it detects a decrease in service in the brake pipe pressure through the SIU. By means of its microprocessor unit, the EOT ES two-way unit responds to this service brake signal by ordering its valve to reduce the pressure of the brake pipe from the last car at the same service speed as that ordered by the system. brake control on the main locomotive at the train head. A brake service application can therefore be performed much faster on a train equipped with a TRAINLINK® ES system or similar EOT type. When using the SIU, the LCU ES can also automatically transmit an emergency brake signal when an emergency decrease in brake pipe pressure has been activated by the brake control system in the locomotive. The emergency lever switch on the LCU ES can also be used to transmit this emergency brake signal. Guided by the American Association of Railways (American Association of Railroads (AAR)), the railway industry, particularly for freight trains, encourages the development of innovative brake control systems based on ECP. This is because the ECP brake control systems develop much better and are much more capable, than their older pneumatic counterparts. A system based on ECP, for example, can apply and release the car brakes much faster than any of the conventional pneumatic brake control systems. For a conventional system, the speed at which the brakes react is relatively slow since it takes time, especially for long freight trains, for the pneumatic brake orders to propagate along the length of the brake pipe. For a system based on ECP, the speed at which the brakes react is much faster so that the brake orders are electrically transmitted to the wagons. In addition, unlike wagons equipped with conventional pneumatic brake equipment, wagons equipped with ECP brake equipment communicate with the locomotive. Not only does it act after the electric brake orders received from the main controller, the ECP brake equipment in each car also reports to the locomotive the previously mentioned ECP data (that is, data about their own operations). As the railroad industry converts to ECP-based brake control systems, it faces several logistical problems typical of such transitions. The first ECP equipped trains put into operation have typically been limited to operate as "ensemble trains" (ie, a group of wagons each equipped with ECP brake equipment and operated as a single train). However, most of the larger railway operation authorities are not able to dedicate only one locomotive to a particular assembly train. For a railroad authority to operate an assembly train on a consistent basis, it would need to equip a larger number than its locomotives with ECP brake control systems. The issues of additional complication are that a given assembly train must frequently travel several territories each operated by a different railway authority. Consequently, a given assembly train can be dragged by several different locomotives en route to their destination. OBJECTIVES OF THE INVENTION It is further a primary object of the invention to provide a conversion system that allows a locomotive equipped with a conventional pneumatic brake control system to control the brakes of wagons equipped with the innovative electrically controlled pneumatic brake equipment ( ECP). Another object of the invention is to provide a conversion system as a portable unit, one that can be installed either in the last locomotive in a group of locomotives or in the first car in an ECP assembly train. Still another objective is to provide a basic version of the invention in which the conversion system is configured to operate on a train without taking full advantage of all the communication capabilities offered by the radio end-of-train (EOT) radio system in the train. Still another object is to provide an improved version of the invention in which the conversion system is configured to operate on a train equipped with a radio end-of-train (EOT) radio system so that data related to ECP can be transmitted further. easily to the train operator. In addition to the aforementioned objects and advantages, various other objects and advantages of the invention will become more readily apparent to those skilled in the relevant art from a reading of the detailed description section of this document. The other objects and advantages will become particularly apparent when the detailed description is considered together with the following drawings and claims. SUMMARY OF THE INVENTION The invention provides a conversion system for enabling a locomotive equipped with a conventional brake control system to control braking in wagons having electrically controlled pneumatic brake equipment (ECP). The conversion system includes two pressure transducers, a mechanism that regulates the pressure, a DC-DC converter, a controller unit and two pressure reduction circuits. The first pressure transducer is used to convert the pressure inside the brake pipe in the locomotive to a first feedback signal indicative of the brake pipe pressure of the locomotive. The second pressure transducer is used to convert the pressure inside the brake pipe in the wagons to a second feedback signal indicative of the pressure of the car brake pipe. The mechanism that regulates the pressure is used to regulate at a predetermined nominal pressure the air that is supplied to the brake pipe of the wagons by means of a main reservoir pipe in the locomotive. The DC-DC converter is used to convert the battery voltage received from a power line in the locomotive to a predetermined nominal voltage with which to ignite an ECP train line in the wagons. Operating in accordance with the instructions contained within the programming code, the controller unit monitors the first and second feedback signals received from the pressure transducers, controls the DC-DC converter and converts the pneumatic brake commands transmitted by the brake pipe in the locomotive to electric brake orders corresponding thereto for transmission along the ECP train line. It is through these electric brake commands that the ECP brake equipment in each car and consequently the available braking effort is controlled. Activated by the controller unit, the first pressure reduction circuit is used to decrease the pressure of the car brake pipe to an emergency level. When a pneumatic emergency brake order appears on the brake pipe in the locomotive, the controller unit (i) activates the first pressure reduction circuit and (ii) transmits an electric emergency brake command along the ECP train line thus ordering both the air brake and the ECP brake equipment to perform an emergency brake application . The second pressure decrease circuit ensures that the pressure of the car brake pipe decreases to the emergency level when the brake pipe pressure of the locomotive falls below a prespecified level. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic view of the pneumatic brake equipment typically found in a wagon of a freight train. Figure 2 is a simplified block diagram of a conversion system, according to the invention, for a conventional pneumatic brake control system of a train. Figure 3 is a block diagram illustrating a particular manifestation of the conversion system shown in Figure 2. DETAILED DESCRIPTION OF THE INVENTION Before describing the invention in detail, the reader is cautioned that, for clarity and understanding, the components Identical functions that have identical functions have been marked where possible with the same reference numbers in each of the figures provided in this document. Although the invention is described below as being deployed with a WABCO 26-L Pneumatic Brake Control System, it should be apparent from a reading of this document that the invention can be incorporated into several other known brake control systems. The invention, for example, can be used with some electronic air brake control systems having pneumatic interfaces identical to the 26-L system. Depending on the particular brake control system with which the invention is used, some modifications of a minor and well known nature may be necessary. Figures 2 and 3 illustrate the essential details of the invention specifically, a conversion system 100 designed to allow a locomotive equipped with a conventional pneumatic brake control system to control the brakes in wagons equipped with electrically controlled pneumatic brake equipment (ECP ). As is apparent from the figures, the conversion system 100 is intended to interconnect the 26-L Brake Control System in the control locomotive and the ECP brake equipment in the wagons. Preferably designed as a portable unit, the conversion system can be installed either in the last locomotive of a group of locomotives or in the first car of an ECP train. Referring to Figure 3, the conversion system 100 includes a first pressure transducer 110, a second pressure transducer 120, a pressure regulating mechanism 130, a DC-DC converter 140, a controller unit 150 and two decrease circuits. of pressure 160 and 170. The first pressure transducer 110 is used to convert the pressure within the brake pipe in the locomotive into a first electrical feedback signal indicative of the pressure of the brake pipe of the locomotive. The second pressure transducer 120 is used to convert the pressure within the brake pipe in the wagons to a second electrical feedback signal indicative of the pressure maintained within the brake pipe in the wagons. The pressure regulating mechanism 130 interconnects the equalization pipe of the main tank (MRE) in the locomotive and the brake pipe in the wagons. Supplied from the MRE line with air maintained at approximately 130 psi, the mechanism is used to supply air and to regulate the pressure within the car brake pipe to a predetermined nominal level of preferably 90 psi under normal operating conditions. The mechanism that regulates the pressure 130 can take the form of a fully pneumatic valve, an electro-pneumatic valve or one of several other means for regulating the known pressure in the brake control technique. If the electro-pneumatic valve is preferred, the controller unit 150 can be used to control the electro-pneumatic valve in order to maintain the brake pipe of the wagons at a predetermined nominal level during non-emergency situations. The DC-DC converter 140 is used to convert the received battery voltage from the locomotive to a predetermined nominal voltage with which to ignite the ECP train line that extends along the wagons. Supplied with the 74vc cc power lines and the return line of the MU line cable, the DC-DC converter 140 converts this voltage to approximately 230V DC. This predetermined nominal voltage is used to ignite the ECP brake equipment in each wagon in the train in a manner known in the art of brake control. Notwithstanding the second pressure decrease circuit 170, the controller unit 150 is used to control the general operation of the invention. On the side of the locomotive of the diagram shown in figure 3, the controller unit is connected to (i) the 74V cc and return power lines of the line cable MU from which it receives power and (ii) the piping of the brake through the first pressure transducer 110. On one side of the car of the invention, the control unit 150 is connected to the brake pipe through (i) of the second pressure transducer 120 and (ii) of the first decrease circuit of pressure 160. The control unit 150 also connects to the DC-DC converter 140 and the line of the ECP train turned on of 230V DC. From the brake line of the locomotive the control unit 150 receives pneumatic service or emergency brake commands through the first pressure transducer 110. Operating in accordance with the instructions contained within its programming code, the controller unit converts these pneumatic brake commands in electric brake orders corresponding thereto. The controller unit then transmits these electric brake commands along the ECP train line to operate the ECP brake equipment in the wagons. For a pneumatic emergency brake command, the conversion system 100 also provides electro-pneumatic and pneumatic backups 160 and 170, respectively, to this electrical control of the ECP brake equipment. Specifically, the conversion system not only transmits the emergency brake command to the ECP brake equipment electrically via the ECP train line, but also transmits the emergency brake command pneumatically through the brake pipe. wagon as described below. In addition, if it loses power or otherwise fails electrically, the conversion system 100 will use only the car brake pipe to transmit a pneumatic emergency brake command to the ECP brake equipment. However, it is via the energized ECP train line with 230V dc that the controlling unit 150 is normally capable of transmitting the electric service and emergency brake orders to the car ECP brake equipment. The first pressure reduction circuit 160 preferably takes the form of a solenoid operated valve which is connected to the brake pipe of the wagons. Depending on how one wishes to be controlled, the pressure reduction circuit 160 may be a normally open solenoid valve, a normally closed solenoid valve or even one of several other known (first) means to decrease the pressure within the brake pipe. of wagon. For the normally open variant, the controller unit 150 can be used to keep the solenoid valve energized, thus normally maintaining the solenoid valve in the closed position. If the control unit detects a pneumatic emergency brake command in the brake line of the locomotive (for example, the pressure below a nominal value of about 30 psi) through the first pressure transducer 110, the controller unit 150 would then be used to de-energize the solenoid valve so that the brake pipe of the car can vent to the atmosphere at an emergency speed.

The normally open solenoid valve would also be de-energized when the controller unit 150 suffers a loss of power. For the normally closed variant, the controller unit 150 can be used to energize (ie, open) the solenoid valve when the pneumatic emergency brake command appears in the brake pipe of the locomotive. No matter which variant is used, it is thought that the first pressure relief circuit 160 vents the car brake pipe to the atmosphere in response to a decrease in emergency pressure in the brake pipe of the locomotive. In the absence of an energy loss, the controller unit 150 monitors the first and second feedback signals received from the pressure transducers and otherwise operates in accordance with the instructions contained in its programming code. Specifically, when the controller unit receives a first feedback signal from the first pressure transducer 110 indicating that a pneumatic emergency brake command has appeared on the locomotive brake pipe, the controller unit will respond as described below. First, the controller unit will transmit an electric emergency brake command to the ECP brake equipment along the ECP train line. The ECP brake equipment responds on each wagon to the emergency brake order in the well-known manner previously mentioned when performing an emergency braking application. Second, the controller unit 150 will simultaneously cause the preferred solenoid valve to decrease the pressure of the car brake pipe at an emergency speed. The second feedback signal from the second pressure transducer 120 is used by the controller unit "to verify this decrease in pressure." Even though the controller unit 150 suffers a loss of energy, the solenoid valve will decrease the pressure of the brake pipe. of the wagon to an emergency level, it is when the pressure in the wagon brake pipe falls to the emergency level that the controller unit either actively or after a loss of energy pneumatically orders the ECP brake equipment in each wagon an emergency application of the brakes The second pressure reduction circuit 170 may take the form of any of the various known means (second) by which the pressure contained within the car brake pipe decreases. of a valve piloted by air, the purpose of the second circuit of pressure decrease is to ensure that the brake pressure of the wagon pipe will decrease to the emergency level when the brake pipe pressure of the locomotive falls below a prespecified level of approximately 45 psi. Specifically, the pilot port of the valve responds to a drop in the brake pipe pressure of the locomotive below the prespecified level by causing the air-operated valve to open. When open, the air-operated valve relieves the car brake pipe to the atmosphere at an emergency speed. Together with the solenoid operated valve 160 or even by itself, the air piloted valve 170 is capable of lowering the pressure in the car brake pipe to the emergency level and thus pneumatically ordering the ECP brake equipment in each wagon perform an emergency application of the brakes. The air piloted valve 170 therefore serves as a fail-safe pneumatic backup to the electronically controlled solenoid operated valve 160. The controller unit 150 can be implemented at least in part in the form of a microcontroller package such as the POWERLINK PROCESSOR manufactured by Pulse Electronics Incorporated, a division of WABCO. Designed to operate with ECP-based brake control systems of the locomotive, this microcontroller package features a microprocessor and power line modem such as the Echelon LonWorks power line modem (PLT-10) currently required by the AAR for ECP communications. In order to operate an ECP assembly train from a locomotive equipped with a conventional pneumatic brake control system, however, the microcontroller package must be extensively modified to perform the functions envisioned by this invention. The microprocessor must be adapted to receive as inputs the first and second feedback signals from the pressure transducers 110 and 120 to monitor the pressure in the brake pipe both in the locomotive and on the sides of the wagon of the invention. The microprocessor must also carry out the conversion of the pneumatic brake commands in their electrical counterparts and control the operation of the first pressure reduction circuit 160. It must also control the operation of the DC-DC converter 140 thus controlling when the power is supplied. ECP train line. Controlled by the microprocessor, the power line modem is used to communicate the ECP data to and from the car ECP brake equipment through the ECP train line. The ECP data includes, of course, the electric brake commands formulated by the microprocessor. In its most basic mode, the conversion system 100 can be configured to work with a conventional pneumatic brake control system to operate an ECP set train without the need to modify the hardware in the locomotive. In this basic mode, the end-of-train radio telemetry (EOT) system is not taken advantage of, particularly its deployment screens, even if they are present. The standard brake line pressure gauge is used to provide the deployment of the braking effort in the same way as was done in the conventionally equipped locomotive. The difference is that the conversion system and the car ECP brake equipment together significantly reduce the time it takes to apply and release the brakes as compared to conventional brake equipment. In addition, with the brake control system of the locomotive placed in the "passenger service" mode of operation, a graduated release of the brakes can also be carried out quickly. In addition, the controller unit 150, through a known communication means, can be linked to the alarm line of the MU line cable in the locomotive. Consequently, the critical data belonging to the alarm conditions relevant to the operation of the ECP brake equipment can be communicated from the controller unit 150 to the brake control system of the locomotive. This critical data can be communicated to the locomotive brake control system through the alarm line with a single on / off sequence to distinguish easily from the alarms activated by the locomotive equipment. By communicating critical data through the alarm line, the train operator in the locomotive can also be alert to the critical conditions that occur in ECP equipped wagons. In a more improved embodiment, the conversion system 100 can be configured to work with a conventional pneumatic brake control system so that the EOT radio telemetry system is taken advantage of in a train. In this mode, a separate EOT transceiver 180 would be used to communicate with the locomotive control unit (LCU) of the EOT radio telemetry system. A radio modem, such as the 1200 bps FFSK model typically included as a part of the microcontroller packet, would be used to encode and decode incoming and outgoing radio communications, respectively, for the microprocessor. Used to link the controller unit 150 to the EOT radio telemetry system, the EOT 180 transceiver and the radio modem would be used to communicate to the LCU the various data pertaining to the operation of the ECP brake equipment. Examples of such data include data pertaining to diagnostics and alarm conditions relevant to the operation of the car ECP brake equipment. Unlike the basic mode, the improved version would require the modification of the programming code executed by the LCU in the locomotive. Only the minor modification would be required for the subsequent EOT unit located in the last car on the train. By modifying the programming code of the LCU, the supplementary display screen of the LCU can be used to visually transmit diagnostic and alarm data to the train operator in the locomotive. In addition, the LCU software can also be modified to increase the ECP data that has traditionally been shown to the operator of a train having conventional pneumatic brake equipment. For example, a panel of the primary LCU display screen has traditionally been used to deploy only the brake pipe pressure in the last car. By appropriate modification of the LCU code, the supplemental display screen can be used to show the percentage that the then existing brake pipe pressure represents the amount required for a full service application based on accumulated data from each ECP equipped wagon. The code of the EOT telemetry system can also be modified so that an established sequence of button pressures can be used to configure the system for operation with the designed 100 conversion system. The microcontroller packages used in brake control systems based on ECP of the locomotive of the prior art use programming code developed before my invention and in accordance with the directives published by the AAR. This existing programming code contains algorithms and control modules that basically refer to the ECP communications discussed in the background section of this document such as the transmission of electric brake commands, ECP operational data and other diagnostic information. Other diverse functions, like adjusting the orders of electrical brake to compensate the wagons whose brakes have been interrupted are handled by the existing code of programming. Accordingly, the controller unit 150 of my invention can also use many of the algorithms and control modules contained within this existing programming code. In addition to the existing programming code, the controlling unit 150 will require new programming code to perform the new various functions described herein. For example, new programming code will be required for (i) monitoring of pressure transducers 110 and 120 and processing of the first and second feedback signals (ii) conversion of pneumatic brake commands to the corresponding electric brake commands; (iii) control of the cc-cc converter 140 and (iv) control of the first pressure reduction circuit 160. Having described my invention herein, it will be suitable within the capabilities of someone of ordinary experience in the brake control technique. encode these new functions in the programming code. Illustrated in Figure 3 is another feature of the invention, namely, a manual override valve 190. If an emergency application of the train brakes is required, the train would be stopped before the conversion system can be restored. If the train carriages are equipped with double pneumatic brake and ECP equipment, the manual override valve 190 can be used to reconnect the locomotive brake pipe with the car brake pipe. The presently preferred embodiments have been established to carry out the invention in accordance with the Patent Law. Those of ordinary experience in the subject matter to which this invention pertains may nonetheless recognize various alternative methods of practicing the invention without departing from the spirit and scope of the following claims. Those with such experience will recognize that the foregoing description is merely illustrative and is not intended to limit any of the following claims to any particular narrow interpretation. Consequently, to promote the progress of science and useful techniques, I assure through the Patent of Privileges the exclusive rights to all matters included in the following claims for the time prescribed by the Patent Law.

Claims (23)

1. NOVELTY OF THE INVENTION Having described the present invention, it is considered as a novelty and therefore the property described in the following claims is claimed as property. 1. A conversion system to allow a locomotive equipped with a conventional brake control system to control braking in wagons having electrically controlled pneumatic brake equipment (ECP), the conversion system comprising: (a) a first transducer pressure to convert the pressure inside a brake pipe of the locomotive into a first feedback signal indicative of the pressure of the brake pipe of the locomotive; (b) a second pressure transducer for converting the pressure within a brake pipe of the wagons into a second feedback signal indicative of the car brake pressure of the wagon; (c) means for regulating at a predetermined nominal pressure the air supplied to the brake pipe of the wagons coming from a main reservoir pipe of the locomotive; (d) a dc-dc converter for converting the received battery voltage from a line of the locomotive's power train to a predetermined nominal voltage to energize an ECP train line of the wagons; (e) a controller unit operating in accordance with the instructions contained within the programming code, for monitoring the first and second feedback signals received from the pressure transducers, controlling the DC-DC converter and converting the pneumatic brake commands by means of the brake pipe of the locomotive in electric brake commands corresponding thereto for transmission along the line of the ECP train and thus controlling the ECP brake equipment in the wagons and thereby the available braking effort; (f) a first means, activatable by the controller unit, to decrease the pressure of the car brake pipe to an emergency level so that when a pneumatic emergency brake command appears in the brake pipe of the locomotive, the controller unit (i) activates the first means and (ii) transmits an emergency electric brake command along the line of the ECP train thus ordering both the pneumatic and electrically the ECP brake equipment to perform an emergency brake application; and (g) a second means to ensure that the pressure of the car brake pipe decreases to the emergency level when the brake pipe pressure of the locomotive falls below a prespecified level.
2. 2. The conversion system, according to claim 1 characterized in that the first means is a normally closed solenoid operated valve connected to the brake pipe of the wagons, the control unit opens the solenoid operated valve when the emergency emergency brake order appears in the brake pipe of the locomotive causing the solenoid operated valve to relieve the pressure of the car brake pipe at an emergency speed.
3. 3. The conversion system, according to claim 1 characterized in that the first means is a normally open solenoid operated valve connected to the brake pipe of the wagons, the solenoid operated valve kept closed by the controller unit unless the controller unit suffers a loss of energy or a pneumatic emergency brake command appears on the locomotive brake pipe in which case the solenoid operated valve relieves the pressure of the car brake pipe at an emergency speed.
4. 4. The conversion system, according to claim 1, characterized in that the second means is an air-piloted pneumatic valve whose pilot port responds to a drop in the brake pipe pressure of the locomotive below the pre-specified level by causing the pneumatic valve opens thus allowing the pressure of the car brake pipe to vent to the atmosphere at an emergency speed.
5. 5. The conversion system, according to claim 1, characterized in that the regulating means includes a valve that regulates the pressure connected between the main reservoir pipe of the locomotive and the brake pipe of the wagons.
6. 6. The conversion system, according to claim 1, characterized in that the means for regulating includes: (a) an electro-pneumatic valve connected between the main reservoir pipe of the locomotive and the brake pipe of the wagons; and (b) the control unit for controlling the electro-pneumatic valve to maintain the brake pipe of the wagons at a predetermined nominal pressure (absent in emergency).
7. 7. The conversion system, according to claim 1 characterized in that the controller unit includes: (a) a power line modem to communicate ECP data to and from the ECP brake equipment of the wagons through the train line ECP, including ECP data transmission of electric brake orders; (b) an EOT transceiver linked to a locomotive control unit in the locomotive for radio communication of the data pertaining to the diagnostic and alarm conditions relevant to the operation of the ECP brake equipment; (c) a radio modem for encoding and decoding radio communications between the EOT transceiver and the locomotive control unit; Y (d) a microprocessor operating in accordance with the instructions contained within the programming code, for monitoring the pressure transducers, which control the conversion of pneumatic brake commands into electric brake commands and controlling the operation of the DC-DC converter, the first medium, the modems and the EOT transceiver.
8. The conversion system, according to claim 1 characterized in that the controller unit includes: (a) a power line modem to communicate the ECP data to and from the ECP brake equipment of the wagons through the train line ECP, including ECP data transmission of electric brake orders; (b) means for communicating the critical data pertaining at least to the alarm conditions relevant to the operation of the ECP brake equipment to the brake control system of the locomotive; and (c) a microprocessor, which operates in accordance with the instructions contained within the programming code, to monitor the pressure transducers, control the conversion of the pneumatic brake commands into electric brake commands and control the operation of the means for communication, the first medium, the DC-DC converter and the power line modem.
9. 9. The conversion system according to claim 8, characterized in that the communication means transmits the critical data to the brake control system of the locomotive through a locomotive alarm train line.
10. 10. The conversion system, according to claim 1, characterized in that it also includes a manual passage valve connected between the brake pipe of the locomotive and the brake pipe of the wagons when the wagons are equipped with both the ECP brake equipment as with the pneumatic brake equipment.
11. 11. A conversion system for enabling a locomotive equipped with a conventional brake control system to control braking on a train whose wagons each have electrically controlled pneumatic brake equipment (ECP), the conversion system comprising: (a) a first pressure transducer for converting the pressure within a brake pipe into a first feedback signal indicative of the pressure of the brake pipe of the locomotive; (b) a second pressure transducer for converting the pressure within a wagon brake pipe to a second feedback signal indicative of the pressure of the wagon brake pipe; (c) means for regulating, at a predetermined nominal pressure, air supplied to a wagon brake pipe coming from a main locomotive reservoir pipe; (d) a controlling unit for monitoring the first and second received feedback signals from the pressure transducers and for converting the pneumatic brake commands transmitted by the locomotive brake line into corresponding electric brake commands for their transmission along an ECP train line of the wagons and thus controlling the ECP brake equipment in each of the wagons and thereby the available braking effort; (e) the first means, activatable by means of a controlling unit, to decrease the pressure of the car brake pipe to an emergency level such that when a pneumatic emergency brake order appears in the brake pipe of the locomotive , the control unit (i) activates the first means and (ii) transmits an emergency electric brake command along the line of the ECP train thus ordering both the air brake and the ECP brake equipment to perform an emergency brake application; and (f) second means to ensure that the pressure of the car brake pipe decreases to an emergency level when the brake pipe pressure of the locomotive falls below a prespecified level.
12. 12. A conversion system for enabling a locomotive equipped with a conventional brake control system to control braking in wagons having electrically controlled pneumatic brake equipment (ECP), the conversion system comprising: (a) conversion means of energy to convert the received battery voltage from a line of the locomotive's power train to a predetermined nominal voltage to ignite the ECP brake equipment of the wagons through an ECP train line; and (b) a signal conversion means for converting pneumatic brake commands issued from the locomotive into electric brake commands corresponding thereto for transmission along the train line ECP thus enabling control of the ECP brake on the wagons and thus the braking effort available.
13. The conversion system, according to claim 12, characterized in that the signal conversion means include: (a) a first pressure transducer for converting the pressure within a brake pipe of the locomotive into a first feedback signal indicative of the pressure locomotive of the brake pipe; (b) a second pressure transducer for converting the pressure within a wagon brake pipe into a second feedback signal indicative of car brake pipe pressure; (c) means for regulating, at a predetermined nominal pressure, air supplied to the brake pipe of the wagons coming from a main reservoir pipe of the locomotive; and (d) a controller unit, operating in accordance with the instructions contained in the programming code, for monitoring the first and second feedback signals received from the pressure transducers, controlling the energy conversion means and converting the pneumatic brake commands transmitted by a locomotive brake line in electric brake orders transmitted along the ECP train line and thus controlling the ECP brake equipment in wagons and thereby the available braking effort.
14. The conversion system, according to claim 13, characterized in that they also include: (e) a first means, activatable by the controlling unit when the brake pipe in the locomotive carries a pneumatic emergency brake order, to decrease the pressure of the the car brake pipe to an emergency level and thus pneumatically order the ECP brake equipment to perform an emergency brake application; and (g) a second means to ensure that the pressure of the car brake pipe decreases to an emergency level when the brake pipe pressure of the locomotive falls below a prespecified level.
15. 15. The conversion system, according to claim 14 characterized in that the first means is a normally closed solenoid operated valve connected to the brake pipe of the wagons, the control unit opens the solenoid operated valve when the emergency emergency brake order appears in the brake pipe of the locomotive causing the solenoid operated valve to relieve the pressure of the car brake pipe at an emergency speed.
16. 16. The conversion system, according to claim 14, characterized in that the first means is a normally open solenoid operated valve connected to the brake pipe of the wagons, the solenoid operated valve maintained closed by a controller unit unless the controller unit suffers A loss of energy or emergency pneumatic brake brake order appears on the locomotive brake pipe in which case the solenoid operated valve relieves the pressure of the car brake pipe at an emergency speed.
17. 17. The conversion system, according to claim 14, characterized in that the second means is an air-piloted pneumatic valve whose pilot port responds to a drop in the brake pipe pressure of the locomotive below the pre-specified level by causing the pneumatic valve opens allowing the pressure of the car brake pipe to vent to the atmosphere at an emergency speed.
18. 18. The conversion system, according to claim 13, characterized in that the regulating means includes a valve that regulates the pressure connected between the main reservoir pipe of the locomotive and the brake pipe of the wagons.
19. 19. The conversion system, according to claim 13, characterized in that the regulating means includes: (a) an electro-pneumatic valve connected between the main reservoir pipe of the locomotive and the main piping of the wagons; and (b) the control unit for controlling the electro-pneumatic valve to maintain the brake pipe of the wagons at a predetermined nominal pressure in the absence of an emergency.
20. 20. The conversion system, according to claim 13, characterized in that the controller unit includes: (a) a power line modem to communicate the ECP data to and from the ECP brake equipment of the wagons through the train line ECP that include the transmission of electric brake commands; (b) an EOT transceiver linked to a locomotive control unit in the locomotive for radio communication of the data pertaining to the diagnostic and alarm conditions relevant to the operation of the ECP brake equipment; (c) a radio modem for encoding and decoding radio communications between the EOT transceiver and the locomotive control unit; and (d) a microprocessor, which operates in accordance with the instructions contained within the programming code, to monitor the pressure transducers, control the conversion of the pneumatic brake commands into electric brake commands and control the operation of the conversion of energy, power line and radio modems and EOT transceiver.
21. 21. The conversion system, according to claim 13, characterized in that the controller unit includes: (a) a power line modem to communicate the ECP data to and from the ECP brake equipment of the wagons through the ECP train line, including ECP data transmission of electric brake orders; (b) means for communicating the critical data pertaining at least to the alarm conditions relevant to the operation of the ECP brake equipment to the brake control system of the locomotive; and (c) a microprocessor, which operates according to the instructions contained within the programming code, to monitor the pressure transducers, control the conversion of pneumatic brake commands into electric brake commands and control the operation of the means for communicate, the modem and the means of energy conversion.
22. 22. The conversion system according to claim 21, characterized in that the means for communicating transmits the critical data to the brake control system of the locomotive through a line of the alarm train of the locomotive.
23. 23. The conversion system, according to claim 12, characterized in that it also includes a manual pass-through valve connected between the brake pipe of the locomotive and the brake pipe of the wagons when the wagons are equipped with both ECP brake equipment and equipment. of pneumatic brake. SUMMARY A conversion system allows a locomotive equipped with a conventional pneumatic brake control system to control braking on a train whose wagons each have electrically controlled pneumatic brake equipment (ECP). The conversion system includes an energy conversion mechanism, a signal conversion mechanism and two pressure reduction circuits. The energy conversion mechanism converts the received battery voltage from a line of the locomotive's power train to a predetermined nominal voltage. Made available on an ECP train line that extends along the wagons, the predetermined nominal voltage is used to turn on the ECP brake equipment on each wagon in the train. The signal conversion mechanism converts the pneumatic brake commands carried on the brake pipe of the locomotive into electric brake commands corresponding thereto. Transmitted along the ECP train line, the electric brake commands control the ECP brake equipment in each wagon and thereby the available braking effort. Part of the signal conversion mechanism uses the first pressure reduction circuit to decrease the pressure of the car brake pipe to an emergency level when the brake pipe in the locomotive carries a pneumatic emergency brake order. The first pressure reduction circuit then pneumatically commands the ECP brake equipment to perform an emergency brake application. The second pressure decrease circuit ensures that the pressure of the car brake pipe decreases to an emergency level when the brake pipe pressure of the locomotive falls below a prespecified level.