Patent Application
20140060979
1. Field of the Invention
The present invention relates to a device, system and method for monitoring the status of a railcar handbrake, and for providing an alert when the car is in motion while the handbrake is applied.
2. Description of the Related Art
Wheel damage in the railroad industry is responsible for significant maintenance costs. A common cause of wheel damage is moving the railcar while the handbrake is applied. If the handbrake is applied when the railcar is moving, the wheels of that car will not turn. Instead, they will slide on the rail, resulting in damage to the wheels, e.g., slid flats, spalling, shelling, etc.
Each railcar typically has a brake rigging on the underside of the railcar that includes an arrangement of rods, levers and chains forming a mechanical linkage connected to brake shoes which can be applied to rub against the train wheels, using friction to slow and stop the train. This brake rigging can be operated by an air cylinder that is part of a centralized train air brake system controlled from a central location, e.g., the locomotive. The air brake system is used to slow and stop entire trains.
Most railroad cars also have manually-operated mechanical hand brake devices that can set and release the brakes. They are used to maintain railcars at rest such as When in the rail yard or at a customer site for loading and unloading. Manually operated handbrake devices typically operate at least a portion of the same brake rigging on the railcar used by the air brake system, bypassing the air cylinder to engage the brake shoes.
In one form, the handbrake has a manually operable hand wheel located on the end of the railcar. The hand wheel is attached through gearing to a rotatable axle which in turn is attached to a chain running down the side of the railcar. The gearing provides mechanical advantage allowing a person to operate the hand wheel. The chain may be directly connected, or via a rod, to a bell crank, or a shive wheel which in turn connects to a chain and top rod that runs under the undercarriage of the railcar, and which ultimately links to the brake rigging. Turning of the hand wheel turns the gear to gather up the chain around the axle, pulling the chain in tension and pivoting the bell crank, which in turn tensions the chain and top rod under the undercarriage of the railcar to operate the brake rigging, and thereby apply the brakes. Sufficient tension will prevent the wheels from turning. Turning the hand wheel in the opposite direction will release the brakes. Other forms of handbrakes include a hand lever that is operated manually to apply tension to the chain or rod that operates the brakes in a similar manner as described above.
Since a handbrake is specific to a single railcar, it is not uncommon for inspectors to overlook an individual railcar when checking to ensure that the handbrakes are released. Thus the railcar may be moved with the handbrakes applied.
The present invention provides a device for monitoring the status of a railcar handbrake having a hand operated handle. The device includes a sensing component mounted near the railcar handbrake. A magnet is mounted on the handbrake bell crank or operating chain at a position such that when the handbrake is engaged, the mounted magnet is sensed by the sensing component. Accordingly, a prearranged level of magnetic field sensing by the sensing component will indicate that the handbrake is engaged. Alternatively, the sensing component can be located on the handbrake bell crank or chain and the magnet can be mounted on a railcar structure near the railcar hand brake. The status of the handbrake, on or off, can be communicated, such as by wireless transmission, to a site away from the railcar. A motion detection device can also be provided. If the hand brake is on and motion is detected, a signal providing an alarm of such condition can be transmitted.
The present invention also provides a method of monitoring and reporting the status of a railcar handbrake. The method includes the following steps: (a) sensing whether the handbrake is engaged via a sensor; (b) detecting motion of the rail car; and (c) if in step (b) it is determined that the brake is on, and in step (c) it is determined that the railcar is in motion, transmitting a signal indicating that the brake is on and the railcar is in motion.
In the drawings;
A typical railcar brake system that includes a handbrake monitoring device of the present invention is now described with reference to
A railcar manually-operated handbrake 22 allows railcar 10 to be held stationary even when separated from a train, and without use of the air braking system. Each railcar 10 would have its own handbrake, which typically includes a hand operated handle 24 attached to the end of the railcar 10. The handle 24 is typically a hand wheel 26 but can take other forms such as a hand operated lever. The handle 24 in this case includes a small gear (not shown) for driving a larger gear 28 which has an axle as is known in the art. The gearing ratio provides mechanical advantage allowing a person to operate the hand wheel. A chain 30 is connected to the axle so as to be capable of being wound around it upon rotation of the axle. The chain is connected to a rod 32 which in turn is connected to a bell crank 34 which converts the vertical movement of the chain 30 on the side of the railcar to horizontal movement underneath the railcar 10. A second chain 36 connected at one end to the bell crank 34 and at its other end to a tie rod 38 that is ultimately connected to the brake rigging 37. It is seen that manual rotation of the handle 24 in one direction pulls the chain 30 upwardly. This in turn rotates the bell crank 34 counterclockwise as shown in
A component of brake monitoring device 40 in the form of a magnet is installed preferably on the handbrake bell crank 34. In the illustrated embodiment, and with further reference to
Sensing component 50 is mounted to a structure 51 formed at an end of railcar 10. Sensing component 50 includes electronic circuitry that senses the proximity of magnet 41. Sensing component 50 is positioned such that, upon handbrake 22 being applied thusly bringing magnet 41 into proximity to sensing component 50. The proximity of magnet 41, will be sensed by sensing component 50. In turn, a signal that the handbrake has been engaged will be sent by sensing component 50.
Electrical circuitry 62 is provided within sensing component 50 for determining the state of the handbrake. The electrical circuitry 62 includes the components and wiring to receive and process the proximity of magnet 41. This can include, but is not limited to, analog and digital circuitry, CPUs, processors, circuit boards, memory, controllers, and other electrical items, as required to sense the proximity of magnet 41, including communication circuitry and devices, GPS circuitry and devices, and motion detection circuitry and devices. In the illustrated embodiment, two circuit boards 62a and 62b are provided, hoard 62a having the magnetic field detection circuitry, board 62b the communications circuitry.
A power source such as batteries is part of 64 the electrical circuitry 62 for providing power thereto. Any suitable power source can be provided. In the preferred embodiment, the power source 64 is provided by two C cell lithium-thionyl chloride battery mounted in sensing device 50.
The preferred embodiment of sensing component 50 further includes a housing 66 supported on the railcar for housing the various components within it, e.g., the electrical circuitry 62 and power source 64. The housing is preferably weatherproof, and made of any suitable material such as a UV rated polymer. The various components are mounted and electrically connected within the housing 66. After the various components are installed within the housing, a potting material 67 is provided to fill the housing 66 to maintain, encapsulate and environmentally seal the components within. Any suitable electrical potting material capable of protecting the electric circuitry and components from the harsh railroad environment can be used, where harsh weather, vibration, mechanical impact, thermal shocks, UV exposure, humidity and abrasion might occur while the device is in operation. Such materials include epoxies, polyurethanes and silicone compounds. A flexible urethane suitable for electrical use and through which wireless signals of the frequencies to be used can be transmitted is preferred.
Referring to
The brake monitoring device 40 can transmit information to the CMU 70 via the wireless communication device 68, or by hardwire. Where a wireless device is used in the monitoring device 40 for communicating with the CMU 70, an ultra low power device operating in the 2.4 GHz frequency band is preferred. Means to register the monitoring device 40 with the CMU 70 so that the monitoring device 40 is recognized by the CMU are known in the art.
An example of a preferred system and method of monitoring and reporting the status of a railcar handbrake is now described with reference to
An additional step can include detecting motion of the railcar 10. This can be done with a motion detection device 72 such as an accelerometer or GPS located in the brake monitoring device 40, such as part of the electrical circuitry 62. If it is determined that the brake 16 is on and motion is detected, a signal/alarm indicating that the brake is on and the railcar is in motion can be transmitted either to the CMU 70 for further processing and/or transmission to the end receiver 78, e.g., locomotive 80 or customer ground based computer system 82. The circuitry 62 of the monitoring device 40 can include the necessary components to make this determination. As discussed above, the motion detection device can be alternatively located in the CMU 70. In such an embodiment, information that the brake is on is communicated from the monitoring device 40 to the CMU. If motion is detected by the CMU 70, and the CMU received a communication from the monitoring device 40 indicating that the brake is on, then the CMU would transmit a signal/alarm indicating that the brake is on and the railcar 10 is in motion.
The transmission of the status of the handbrake 22 to the end receiver 78 can be by any known means, e.g., via satellite 86, cell phone system 88, etc. If the transmission is to be sent to the locomotive 80, a direct transmission from the CMU 70 or monitoring device 40 could be used, although due to power requirements, it is preferred in the illustrated embodiment to have the monitoring device 40 transmit low power signals to the CMU.
The monitoring device 40 is preferably installed anywhere in the handbrake mechanism.
In operation, the monitoring device 40 can sample the sensing component 50 intermittently to preserve power and increase battery life. For example, in one embodiment the monitoring device 40 powers up every 30 seconds to read the strain gauge 60. Any other sample period can be used, e.g., 5 second periods are used in another embodiment.
If the brake monitoring device 40 senses that the handbrake is applied, and railcar motion is detected, a signal/alarm is transmitted. Where the motion detector is included in the CMU 70, the information indicating that the handbrake is on is communicated from the monitoring device 40 to the CMU 70, via wired or wireless transmission. If the CMU 70 determines that the railcar 10 is in motion, with both conditions now satisfied brake is on and railcar motion detected, the signal/alarm is sent to the desired receiving location 78. The alarm is preferably transmitted using various known means. There are various means to detect motion, one example using a GPS system 92 to monitor for movement of the railcar a certain distance, such as 50 feet upon which the railcar is considered to be in motion.
As discussed above, the present invention provides a handbrake monitoring device, system and method. One key feature and advantage is the ability to monitor the handbrake and, if it is determined that the handbrake is on and the railcar is in motion, a signal/alarm is sent warning that corrective action is required. Also, regular samples of the status of the brake can be made and transmitted. In a preferred embodiment, the monitoring device can work with a CMU, but it is contemplated that the monitoring device can contain the suitable components to act as an individual unit.
