1. Field of the Invention
The present invention relates to generally to electrically powered model vehicle systems, for example, model toy railroad layouts. More particularly, this invention relates to a model toy railroad accessory having an axle-actuated switch.
2. Description of Related Art
Model trains and other model vehicles are known in the art. Electrically powered model trains may include an electrical motor that receives power from one or more rails of a model train track. A transformer may be used to apply the power to the rail while contacts such as a roller or rollers on the bottom of the train or the metallic train wheels pick up the applied power for the train motor. In an AC system such as an O-gauge system, the transformer may control the amplitude of the applied power waveform, thereby controlling the speed and direction of the train. In a DC system such as an HO system, the polarity of the voltage may be controlled to achieve the same or similar results. In O-gauge systems, the track voltage is an AC voltage transformed by the transformer from 60 Hz, 120 volt AC line voltage provided by a standard wall socket, to a reduced AC voltage (e.g., 0-18 volts AC).
Over the course of time, model railroad layouts and accessories have been improved to provide enhanced user control, increased features, and heightened levels of realism. One such area of development has been in model train accessories. Model train enthusiasts now have many electrically-powered trackside accessories from which to choose from in building their customized layout. For example, users may choose from, among others, accessories such as light towers, station platforms, lumber loaders, drawbridges and railroad crossings. These accessories may be powered by the same transformer that powers the electric train. Such accessories are often designed to provide an added degree of realism to the overall model train layout by resembling at a much-reduced scale the appearance and operation of actual railroad auxiliary equipment.
Notwithstanding their advantages, model train accessories may be subject to certain limitations. For example, conventional track-side accessories are connected to the transformer or other power source via a separate circuit. The separate circuit permits the accessory to be controlled independently of the track voltage, but also requires laying cables, connectors, or other circuit elements between each accessory and the power source. The presence of these circuit elements may detract from achieving a desired degree of realism in the track layout. In the alternative, additional effort is required to conceal the circuit elements within the layout.
On the other hand, if a conventional accessory is connected directly to the power supply rails of the track, it may not be controlled independently. That is, such accessories are turned “ON” when the voltage is applied to the track, and remain “ON” until the voltage is removed from the track. In some instances, it may not be necessary, nor may it comport with the goal of realism, to have an accessory running all the time. In this situation, an accessory that remains “ON” all the time results in a lowered level of realism, as well as an inefficient use of electricity.
Accordingly, a need exists for a system comprising a railroad accessory that overcomes these and other deficiencies of the prior art.
The present invention provides a system for providing power to a model vehicle accessory, that overcomes the limitations of the prior art. The system provides for connecting an accessory directly to an electrically-powered rail of a model track assembly, while permitting power to the accessory to be controlled independently of the powered rail.
In an embodiment of the invention, the accessory is of a type intended to operate as a model train approaches it, and to cease operating when the model train departs. Many accessories fall into this category, for example, crossing signals, crossing gates, drawbridges, loaders, and so forth. The system includes a switch configured to respond to the approach of a model train. As the model train approaches the accessory, the switch is activated to provide electrical power to the accessory from the powered rail of the track assembly. The same switch, or a second switch, may be configured to be activated as the model train departs from the accessory, cutting off electrical power and deactivating the accessory.
In a three-rail AC system such as an O-gauge system, the accessory system may be configured for power control using an axle-actuated switch. Three-rail systems typically comprise a power rail, a neutral rail, and an electrically isolated rail. The power rail may comprise an inner rail of the three parallel rails. A special centrally-located wheel or roller may therefore be used by a model vehicle to make contact with the power rail, while most of the wheels of the model vehicle rest on the electrically neutral and electrically isolated outer rails. The model vehicle may additionally be provided with one or more electrically connected wheel pairs, for example, two wheels connected by an axle comprising a metallic or other conductive material. Each wheel pair may be configured to provide a rolling electrical connection between a pair of rails, such as between a neutral rail and an electrically isolated rail, or between the power rail and the electrically isolated rail. A wheel pair may be disposed at different locations on a model vehicle, for example, on the front of a model locomotive or rear of a caboose, or on each model car of a model train, or at multiple locations on a car.
A track layout may comprise a plurality of mechanically-connected blocks of track. Each block may be connected to adjacent blocks using an electrically insulating mechanical connector for each rail. In this way, power to each block of track can be separately controlled. In the alternative, or in addition, the power and neutral rails of a three-rail layout may be electrically and mechanically connected in adjacent blocks, while the electrically insulating connecter is used to join the electrically isolated rail of adjacent blocks. Either way, a section of the electrically isolated rail adjacent to the accessory may be electrically isolated from adjacent sections of the rail (e.g., in an adjacent block of track) using an insulating mechanical connector. A power supply circuit for the accessory may be connected to the neutral rail and to the electrically isolated rail of the adjacent section of track. Therefore, when no model vehicle is present on the track section, no power is supplied to the accessory, which therefore remains inactive.
When a model vehicle equipped with the electrically-connected wheel pairs enters the track section adjacent to the accessory, one or more wheel pairs connects the electrically isolated rail to either of the neutral rail or the power rail, thereby supplying power to the accessory. The accessory is therefore activated while the model vehicle, or more precisely, a connected wheel pair, is present on its associated track section. When the model vehicle leaves the track section, the electrically isolated rail is cut off from the power circuit, and the trackside accessory is inactivated. Thus, accessories such as signal crossing lights or gates may easily be made to respond to the presence of a model vehicle, without requiring any external control wiring.
In an embodiment of the invention, a model vehicle accessory in accordance with the present invention includes a housing having a first end and a second end opposite the first end. The present invention further includes a model vehicle track section supported by the housing, wherein the track section includes three rails: an electric power rail, an electrically neutral rail, and an electrically isolated rail, each of which extends from the first end of the housing to the second end of the housing. The housing may be configured to match housing of a standard track section. A power supply circuit may be disposed in or adjacent to the housing, to connect the neutral and isolated rails of the track section to the electronic components, such as lights, sound generators, motors, or other actuators, of the accessory. The electrically isolated rail of the track section may be connected to adjacent sections using an electrically insulating connector. The accessory device may be attached to the housing using a permanent or removable connection.
Thus, according to the later embodiment, a hobbyist may install a vehicle-responsive accessory merely by placing the disclosed housing with its connected track section in a model track layout at the desired location. The electrically isolated rail should then be connected to adjacent sections using an electrically insulating connection, while conductive connectors may be used for the remaining rails, which may be connected to any suitable power transformer in a conventional fashion. When a model vehicle with suitably configured wheel pairs enters the accessory track section, the accessory will be activated so long as a wheel pair remains in the section. No external wiring or controls are required.
A more complete understanding of the model accessory power system will be afforded to those skilled in the art, as well as a realization of additional advantages and objects thereof, by a consideration of the following detailed description of the preferred embodiment. Reference will be made to the appended sheets of drawings which will first be described briefly.
The present invention provides a system for controlling operation of a model vehicle accessory, that overcomes the limitations of the prior art. The system provides for connecting an accessory directly to an electrically-powered rail of a model track assembly, while automatically controlling power to the accessory independently of the powered rail. In the detailed description that follows, like element numerals are used to indicate like elements appearing in one or more of the figures.
Model railroad layout 10 may comprise a model railroad track 12, a power source 14, and a model electric toy train 16. In an exemplary embodiment, track 12 comprises a three rail track. Power source 14 provides power to track 12 by way of connectors 18 and 20 wherein the power terminal of the power supply is connected to the center or third rail of track 12 and the neutral terminal is connected to one or both outer rails of track 12. A two-rail track may also be suitable, coupled with a third conductor running alongside the track. Train 16 may be configured with rolling or sliding contacts for making an electrical connection to one or more rails of track 12. In the alternative, or in addition, train 16 may comprise an arrangement of metallic wheels and conductive axles to provide an electrical connection between the powered rails and an electric circuit of train 16.
Power source 14 may comprise a conventional AC or DC transformer, depending on the requirements of model vehicle 16, or other suitable power supply. Additionally, power source 14 may provide a fixed output, a variable output, or both. In an exemplary embodiment, railroad layout 10 may comprise an O-gauge layout, while power source 14 may comprise an AC transformer which transforms typical AC line voltage (e.g., 120 VAC) to a reduced level (e.g., 0-18 VAC for a conventional O-gauge variable output model train transformer) and supplies the same to track 12.
With reference to
Track section 26 may comprise a three rail track having a first outer rail 36, a second outer rail 38, and a center rail or third rail 40 disposed between the outer rails 36, 38. The illustrated length of the track section 26 is merely exemplary, and either shorter or longer sections may be suitable for particular applications. In addition, section 26 may comprise two or more connected sub-sections of track (not shown). One of the rails, e.g., in the illustrated embodiment rail 38, should be electrically isolated from the corresponding rail of adjoining track sections 42, 44 (Shown in
As already noted, second outer rail 38 should be electrically isolated from corresponding second electrically neutral outer rail of adjoining track sections. To electrically isolate rail 38 while providing a mechanical connection, suitable non-conductive connectors 46, 48 may be used (shown in
With further reference to
Circuit 30 may comprise conventional analog or digital circuitry configured to control the operation of railroad crossing 28. In an exemplary embodiment, circuit 30 is positioned within or under track bed 24. This may provide a neater or more realistic appearance by concealing electrical connections and circuitry. In the alternative, a lock-on or other connector may be used to connect electronics 30 to rails 38, 40 from above track 12. In this case, it may be desirable to conceal the electronics 30 inside a housing of the model trackside accessory 28, or in an adjoining housing.
Circuit 30 may be electrically connected between the center or power rail 40 and isolated rail 38 of track section 26. The neutral rail 36 may be spaced apart a distance that is substantially the same as the length of the axles used on model vehicle 16. Model vehicle 16 may be provided with at least one wheel pair 50. For example, every car of the vehicle may be provided with several such wheel pairs. Each wheel of a pair may be electrically connected to its counterpart by an axle comprising an electrically conductive material. Thus, when an electrically conducting wheel and axle arrangement 50 of train 16 is present on track section 26, it bridges neutral rail 36 and isolated rail 38 of track section 26, providing an electrical connection between them. A power supply circuit is thereby completed, energizing circuit 30, which activates the crossing signal 28 (or other desired accessory). Electronics 30 remains energized and accessory 28 remains activated so long as at least one conducting wheel pair 50 bridges neutral rail 36 and isolated rail 38 in section 26, whereby lamps 58, 60 may be illuminated. When model vehicle 16 completely passes through the crossing area and is no longer present on section 26, the isolated rail 38 returns to an isolated state. Circuit 30 is thereby de-energized, and so the accessory ceases operation after train 16 passes.
With reference to
In addition, or in the alternative, circuit 30 may be configured in various different ways so as to delay or prolong the action of accessory 28 caused by energizing circuit 30. For example, a timer or any other suitable element may be used to delay operation of the accessory when the circuit is energized. Likewise, an energy storage device such as a capacitor may be used to prolong operation of the accessory after a train departs from the connected rail section 38. For example, to prevent a crossing gate from being deactivated in an undesirable position, e.g., any position other than open, electrical or mechanical elements may be provided to return the gate to an open position, no matter what the position of the gate when power is shut off by the departure of the passing model vehicle.
One of the advantages of the circuit shown in
An accessory circuit may include various different elements operated using power from circuit 30. With reference to
Accordingly, there, is disclosed a method 100 for controlling operation of a trackside accessory, exemplary steps of which are diagrammed in
While wheel pairs of a model vehicle may provide a particularly convenient and elegant connector for energizing a trackside accessory as described above, the invention is not limited thereby. Any other form of rolling or sliding contact may also be suitable. In the alternative, a mechanical switch may be provided in the track bed, and configured to make a connection between the power or neutral rails and a trackside accessory when closed by a passing model vehicle. For example, a locomotive may be provided with an actuator on a lower surface that closes a mechanical switch as the locomotive passes by, completing an electrical connection. A counterpart actuator on a trailing car may open the mechanical switch, cutting off power to the accessory. Yet another approach may be to employ an optical or infrared sensor that is responsive to a passing model vehicle. A control circuit as known in the art may then be used to complete an electrical circuit and activate the accessory when the model vehicle is in sensor range.
Having thus described a preferred embodiment of system for controlling operation of a model vehicle accessory, it should be apparent to those skilled in the art that certain advantages of the within system have been achieved. It should also be appreciated that various modifications, adaptations, and alternative embodiments thereof may be made within the scope and spirit of the present invention. For example, a system using vehicle wheel pairs to make a connection between a neutral rail and an isolated rail has been illustrated, but it should be apparent that the inventive concepts described above would be equally applicable to systems that use other connectors, or that connect the isolated rail to the power rail. The invention is further defined by the following claims.