1. Field of the Invention
The present invention relates to electric-powered model vehicles, such as model trains, and more particularly, to a tilting car for a model train or other model vehicle.
2. Description of Related Art
Various model trains and vehicles are known in the art, which model an actual or imaginary train or vehicle at a reduced scale. In a typical model layout, a model train having an engine is provided. The model train engine includes an electrical motor that receives power from a voltage that is applied to model railway tracks. A transformer is used to apply the power to the tracks, while contacts (e.g., a roller) on the bottom of the train, or metallic wheels of the train, pick up the applied power for the train motor. In some model train layouts, the transformer controls the amplitude, and in a DC system, the polarity, of the voltage, thereby controlling the speed and direction of the train. In HO systems, the voltage is a DC voltage. In O-gauge systems, the track voltage is an AC voltage transformed by the transformer from a household line voltage provided by a standard wall socket, such 120 or 240 V, to a reduced AC voltage, such as 0-18 volts AC.
Some model train cars include a tilting function, to provide greater stability when a train is traversing a curve, and to provide a more realistic simulation of an actual train. When actual passenger train cars traverse a curved portion of track at a high rate of speed, the resulting centrifugal forces may cause discomfort or safety risks for the occupants of the train car. Some passenger train cars are therefore equipped to tilt in the direction of the curve, so as to counteract these centrifugal forces. Model train cars may therefore also be designed for tilting, to achieve a higher degree of realism. In addition, a tilting mechanism may be useful to prevent model trains from derailing when traversing curves at high speed.
Notwithstanding these advantages, however, prior-art model trains with tilting mechanisms may be subject to certain limitations. For instance, conventional model trains achieve the tilting functionality using mechanical arrangements that lack optimal precision of control. The train car may not tilt to the desired degree at the desired time, which may result in derailment or decreased realism. For example, prior-art tilting mechanism will cause the same degree of tilting regardless of train velocity, which detracts from realism of the tilting effect. Furthermore, prior-art model trains with tilting mechanisms do not permit a user to tilt a train on command, and may require movement around a curved section of track to initiate tilting.
Accordingly, a need exists for a model train with a tilting mechanism that overcomes these and other limitations of the prior art.
The invention provides a model train car with an electronically controlled tilting mechanism configured to control tilting in any direction in response to velocity and track geometry, or in response to a user-issued command. A model vehicle in accordance with the present invention comprises a gear-driven pivoting coupling, which connects a model car body to wheel assemblies, also called “trucks,” for the model car. The position of the pivoting coupling determines the tilt angle of the car body, and is in turn determined by a gear train driven by an electric motor. A tilt sensor is coupled to the car body and is connected to a tilt controller. The electric motor is driven by a control system that includes a programmable controller or control circuit that controls the electric motor, and hence, the tilt angle of the car, in response to input from the tilt sensor.
Further input to the control system may be provided by a position sensor disposed to sense the position of a coupling member, such as a drawbar for pulling the train car. When traversing a straight section of track, the drawbar is pulled substantially straight ahead. When traversing a curve, the drawbar is pulled either to the left or to the right, to an extent related to the radius of a curve. The position sensor is configured to provide a signal to the control system indicative of the position of the drawbar. The controller interprets the signal as indicating the direction and optionally, a degree of curvature of the track being traversed by the model car, and sends an appropriate control signal to the electric motor. The electric motor provides an appropriate output to the gear train, until the body of the car is tilting at an angle deemed appropriate for the curve being traversed.
In an embodiment of the invention, the angle of tilt may also be determined by the velocity of the car. It may be desirable to provide a greater degree of tilt when the car is moving quickly, and a lesser degree of tilt, or no tilt, when the car is more slowly. Accordingly, a velocity sensor may be connected to the tilt control system, and the controller may be configured to adjust the amount of tilt based on the velocity of the train in addition to the position of the coupling member.
In an embodiment of the invention, the title mechanism may also be controlled using user input, such as input from a remote control keypad or other user interface. For example, a user may select a range of operation for the tilt mechanism. In addition, or in the alternative, a user may control the tilt mechanism manually by sending commands via the user interface. Commands may be transmitted from a remote interface to the model train using any suitable wireless transmission method.
A more complete understanding of the model vehicle with a tilting mechanism 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.
FIGS. 9A-C are schematic side views illustrating operation of a tilt mechanism in accordance with the present invention.
The present invention provides a model vehicle with an electronically controlled tilting mechanism, that overcomes the limitations of the prior art. In the detailed description that follows, like element numerals are used to indicate like elements appearing in one or more of the figures.
Train car 26, comprising a tilt mechanism as described herein, may be connected to a controller or receiver in locomotive 24 via a wire or wireless connection. Elements of a control system for the tilt mechanism, or for train 16 generally, may be housed in a trackside control box 18. Control box 18 may transmit control signals via connectors 67, 68 through track 12 to train 16. Suitable transmission methods may include, for example DC-offset or RF signaling. The arrangement described above is for exemplary purposes only and is not meant to be limiting in nature.
With continued reference to
Any suitable pivoting support may be used. For example, support 30 may be pivotally coupled to truck 28 using a single pivot point (not shown), or a plurality of pivot points. In the exemplary embodiment illustrated in
Train car 26 may comprise a second truck 104 and second support 106, in addition to the structure set forth above. In this embodiment, second support 106 is pivotally coupled or pinned to second truck 104 at one or several pivot points. In the illustrated embodiment, support 102 is coupled at four pivot points 1081, 1082, 1083 and 1084. Second truck 104 and second support 106 may be spaced a distance from truck 28 and support 30; and, as with support 30, train car body 32 is positioned on and supported by support 106. In the exemplary embodiment shown in
In the illustrated two-truck arrangement, train car body 32 is supported at one end by support 30 and at the other end by second support 106. Only one of the supports need be driven by a gear train providing a motor torque for tilting, while the other support may be passive. In the alternative, each support may be driven by a gear train receiving input from a motor. The same amount of torque and rotation may thereby be provided to both supports 30, 106, which therefore move in unison to tilt car 32. Other arrangements and spacing of the truck and supports that carry out the above functionality remain within the spirit and scope of the present invention. For example, more than two trucks or supports may be added for further support and precision. Exemplary gear trains for rotating the car supports are described below in connection with
A velocity sensor 35 may also be connected to controller 36 and configured to sense the speed of train 16. In actual trains, the train car does not tilt until a defined speed (i.e., 25 miles per hour scaled speed, for example) is reached. Accordingly, in order to achieve optimum realism, velocity sensor 35 may be configured to sense the speed of train 16 and to generate a speed signal 37 in order determine when a predetermined scaled speed is reached. The use of velocity sensor 35 allows for the automatic tilting of train car body 32 only when a predetermined speed has been reached.
In an exemplary embodiment, velocity sensor 35 comprises a magnet and hall effect sensor positioned on truck 28 of train car 26. The magnet and hall effect sensor may be arranged such that as the magnet rotates with the wheel axle, the hall effect sensor generates signals corresponding to the frequency of rotation, thereby sensing the speed of the train. In the alternative, velocity sensor 35 may comprise a conventional velocity sensor mounted proximate to the drive motor of train 16. In this configuration, velocity sensor 35 is arranged so as to read the speed of the drive motor output shaft, and then generate a speed signal 37 that is delivered to controller 36.
The system may further comprise a tilt sensor 103 operatively connected to controller 36. Tilt sensor may comprise any suitable sensor capable of providing a signal from which an amount of tilt of car body 32 may be determined. For example, an accelerometer or other gravimetric sensor may be used. In the alternative, the tilt of the car body may be determined from motion of the tilt mechanism, for example, by sensing a degree of rotation of the input motor shaft. According to yet another alternative, tilt sensor 103 may comprise a limit switch that provides a signal when tilting of the train car has reached predetermined limits. A signal from the tilt sensor may be provided to controller 36 as end-actuator feedback for controlling motor 38.
Position sensor 34, velocity sensor 35, and tilt sensor 103 may be operably connected to controller 36, whereby first and second curve position signals 50, 54 and speed signal 37 may be sent to or received by controller 36. Controller 36 is operable to receive input signals and to emit output signals, and may be operably associated with a memory within which data and program instructions may be stored. For example, controller 36 may comprise a microcontroller, a microprocessor, any suitable circuit comprising a programmable logic controller, or a circuit comprised entirely of analog devices. Controller 36 may also be configured to control other aspects of model train operation, including but not limited to operation of a main drive motor and various train accessories. In the alternative, controller 36 may be dedicated to operation of the tilt mechanism.
In response to position signals 50, 54 or speed signal 37 (e.g., when the speed of train 16 exceeds a predetermined threshold), controller 36 may be configured to generate a control output 66 for controlling motor 38. Various circuits and suitable control outputs for motor control are known in the art, and any suitable method of motor control may be used. For example, control output 66 may comprise a clockwise (CW) command signal and a counter clockwise (CCW) command signal for a motor controller. When control output 66 is provided to motor 38, an output shaft of motor 38 may rotate in either a clockwise or counter clockwise direction. In an exemplary embodiment, motor 38 may comprise a DC motor that is mounted to train car body 32 or to a frame of car 26. Controller 36 may also be configured to change the direction of rotation of motor 38, as will be discussed in detail below.
In addition to those features set forth above, controller 36 of train car 26 may also be configured to receive user input commands. Controller 36 may be further configured to generate the control output 66 in response to those user input commands, thereby causing body 32 of train car 26 to tilt whenever desired, regardless of whether the train is turning, traveling straight or standing still. For example, a user may command body 32 of train car 26 to tilt in either direction by way of remote control or by way of control box 18 (shown in
Various methods may be used to communicate with the tilt controller. One method of transmitting the input signal is to use a DC protocol, comprising superimposing DC offsets on the AC voltage signal supplied to track 12 by power source 14. In this mode, when controller 36 detects a DC offset, it may generate a control output 66 to activate or deactivate the corresponding feature (i.e., to tilt train 16 in one direction or another). This conventional protocol comprises sending positive and negative DC offsets to controller 36. The different polarities and amplitudes of the DC offsets correspond to different features of train 12, and accordingly, are each operative to activate at least one of the features. In this approach, control block 18 includes a selection device, such as a pushbutton, that a user can use to select the desired feature and functionality.
Another suitable method may comprise using command control as known in the art for model trains. For example, U.S. Pat. Nos. 5,251,856, 5,441,223 and 5,749,547 to Young et al. disclose, among other things, providing a digital message, which may include a command, to train 16 using various techniques. The digital message(s) so produced may be read by controller 36, which may then execute the command by generating control output 66. This protocol allows a user to activate and deactivate features, such as for example, tilting train 16 in one direction or another, with control box 18 or by remote control. For example, using a suitably configured remote control device for a model train, a user may send a tilt command to control box 18, which then sends a corresponding digital message along track 12, which is then picked up by controller 36. A user may also select the desired action by way of a selection device on control box 18, which then transmits the digital input signal along track 12 to controller 36. It is foreseeable that a user may also send input signals by way of remote control to controller 36 itself, thereby bypassing control box 18 altogether. Those skilled in the art will appreciate that any other approach wherein a command can be generated, transmitted, and received may also be suitable for the above described purpose.
With reference to
With reference to
In the illustrated embodiment, first spur gear 72 is in mesh with and driven by first worm gear 70. First spur gear 72 is also coupled with second spur gear 74 by way of a axial shaft, such that the rotation of first spur gear 72 causes second spur gear 74 to rotate. Second spur gear 74 is in mesh with teeth disposed at a first end 84 of rack gear 76, and is configured to drive rack gear 76 in a first and second direction, depending on the direction of rotation of the output shaft, along a horizontal plane 86 defined by rack gear 76. Teeth disposed at a second end 88 of rack gear 76 are in mesh with third spur gear 78 disposed on horizontal plane 86, such that the movement of rack gear 76 is translated to third spur gear 78. Third spur gear 78 is further coupled to a rod 90 disposed perpendicular to horizontal plane 86 and within a pair of U-joints 92, 94, so that as third spur gear 78 rotates, rod 90 also rotates. Rod 90 is further coupled to and configured to drive second worm gear 80, which is positioned directly below third spur gear 78. Accordingly, as third spur gear 78 and rod 90 rotate, second worm gear 80 also rotates. The rotation of second worm gear 80 is then translated to a slotted spur gear 82 that is in mesh with and driven by second worm gear 80.
Exemplary operation of the pivoting support 30 is further illustrated by
An added advantage provided by gear set 40, and gears 78 and 80 in particular, is the stabilization of train car body 32 when train 16 is traveling slower than the predetermined threshold speed required to cause train car body 32 to tilt. The gears are arranged in such a manner that the turning or pivoting of truck 28 does not result in noticeable tilting of support 30 or train car body 32, increasing the level of realism. To provide a noticeable degree of tilting, substantial rotational input from motor 38 should be required.
One of ordinary skill may devise alternative gear trains or other motion transformation systems such as belt or chain drives to transform motion from motor 38 to pivoting of support 30. For example, in an alternative embodiment, first worm gear 70 of gear set 40 may be replaced by a pinion gear 100 that is associated with the output shaft of motor 38, as shown in
Similarly, tilt sensor 103 may comprise a second electrical contact pair 107 for signaling an opposite tilt limit. As train car body 32 tilts to the right, rack 76 moves towards contacts 107 until U-shaped contact 111 bridges the contact pair. When the members of the contact pair 107 are thus connected, controller 36 interprets the state of the paired contacts as indicating that train car body has reached maximum tilt to the right, and causes motor 38 to stop rotating.
Sensor 103 may likewise comprise an electrical contact pair 109 for signaling an upright or center position of train car body 32. When the train car 26 is being tilted back towards the center position, the contact pair may be used to signal the motor to stop. For example, when the train car is coming out of either a left or a right turn, motor 38 may be reversed so as to tilt train car body 32 back to an upright position. Rack 76 moves towards contacts 109 until U-shaped contact 111 bridges the contact pair. Controller 36 may interpret the state of the paired contacts 109 as indicating that train car body is upright, and cause motor 38 to stop rotating.
Operation of a tilting mechanism and control system may therefore be summarized as follows. As a train comprising a plurality of train cars enters a curved portion of track, a coupling member for each car traversing the curve is pulled in the direction of the curve. As the coupling member reaches a predetermined rotational position, an electrical contact disposed on the coupling member makes contact with an electrical contact disposed on the train car. This contact indicates the turn direction to a controller. If the sensed speed of the train is above a predetermined threshold, the controller then generates a control signal for driving a tilt mechanism motor in the direction of the turn. The motor turns an output shaft in the direction indicated by the control signal. The rotation of the output shaft then drives a gear set that is coupled to a support, and causes the support to tilt into the turning direction of the train. The motor continues to rotate until a predetermined limit of tilt is reached, as indicated by a feedback signal received by the controller. When the train comes out of the turn and starts to straighten out, the coupling member moves to the center, away from the electrical contact. In response, the controller reverses the motor direction, causing the train car to turn upright until the tilt limit sensor sends a signal to the controller indicating that the upright position of the train car body has been reached, at which time the operation of the motor is ceased.
Having thus described a preferred embodiment of a model vehicle with an electronically-controlled tilt mechanism, 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 particular tilt mechanism has been illustrated, but it should be apparent that the inventive concepts described above would be equally applicable to other mechanisms arranged according to the spirit and scope of the invention. The invention is defined by the following claims.
This application claims priority pursuant to 35 U.S.C. § 119(e) to U.S. Provisional Application No. 60/575,264, filed May 28, 2004, which application is specifically incorporated herein, in its entirety, by reference.
Number | Date | Country | |
---|---|---|---|
60575264 | May 2004 | US |