Abstract:
A control and motor arrangement in accordance with the present invention includes a motor configured to generate a locomotive force for propelling the model train. The control and motor arrangement further includes a command control interface configured to receive commands from a command control unit wherein the commands correspond to a desired speed. The control and motor arrangement still further includes a plurality of detectors configured to detect speed information of the motor, and a process control arrangement configured to receive the speed information from the sensors. The process control arrangement is farther configured and arranged to generate a plurality of motor control signals based on the speed information for controlling the speed of said motor. The control and motor arrangement yet still further includes a motor control arrangement configured to cause power to be applied to the motor at different times in response to the motor control signals.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application is a Continuation of U.S. application Ser. No. 09/702,466, filed Oct. 31, 2000, now pending and hereby incorporated by reference in its entirety, which is a Continuation-in-Part of U.S. application Ser. No. 09/185,558 filed Nov. 4, 1998, now abandoned. 
     
    
     FIELD OF THE INVENTION  
       [0002]     The present invention relates to model railroads. More particularly, the present invention relates to control and motor arrangements for use in model trains.  
       BACKGROUND  
       [0003]     Model train systems have been in existence for many years. In a typical model train system, the model train engine is an electrical engine that receives power from a voltage that is applied to the tracks and picked up by the train motor. A transformer is used to apply the power to the tracks. The transformer controls both the amplitude and polarity of the voltage, thereby controlling the speed and direction of the train. In HO systems, the voltage is a DC voltage. In Lionel® systems, the voltage is an AC voltage transformed from the 60 Hz line voltage provided by a standard wall socket.  
         [0004]     Some conventional types of model train systems are susceptible to performance degradation related to track irregularities. For example, uneven portions of the track can cause the model train to intermittently lose contact with the track, causing power to be inadvertently removed from the train. Unwanted stopping can result. In addition, upward and downward grades in the track can cause the model train to travel slower or faster than desired due to the effects of gravity. Moreover, certain model train systems fail to adequately simulate the effects of inertia. For example, in some systems, when power is removed from the train, the train stops moving immediately. By contrast, real world trains do not stop immediately when brakes are applied. Accordingly, in some model train systems, play-realism is reduced by these sudden stops.  
       SUMMARY OF THE INVENTION  
       [0005]     A control and motor arrangement installed in a model train is presented. A motor control arrangement in accordance with the present invention includes a motor configured and arranged to generate a locomotive force for propelling the model train. The control and motor arragement further includes a command control interface configured to receive commands from a command control unit wherein the commands correspond to a desired speed. The control and motor arrangement in accordance with the present invention still further includes a plurality of detectors configured to detect speed information of said motor and a process control arrangement configured to receive the speed information from the plurality of sensors. The process control arrangement is further configured and arranged to generate a plurality of motor control signals based on the speed information for controlling the speed of said motor. The control and motor arrangement in accordance with the present invention yet still further includes a motor control arrangement configured to cause power to be applied to the motor at different times in response to the motor control signals. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]     These and other aspects and advantages of the present invention will become apparent upon reading the following detailed description and upon reference to the drawings, in which:  
         [0007]      FIG. 1  illustrates an example control and motor arrangement installed in a model train, according to an embodiment of the present invention;  
         [0008]      FIG. 2  is a profile view, in section, of an example control and motor arrangement for use in a model train, according to another embodiment of the present invention;  
         [0009]      FIG. 3  is a plan view of an example control and motor arrangement for use in a model train, according to another embodiment of the present invention;  
         [0010]      FIG. 4  is a block diagram illustrating an example control arrangement forming part of a control and motor arrangement for use in a model train, according to yet another embodiment of the present invention;  
         [0011]      FIGS. 5A and 5B  are portions of a schematic diagram depicting an example circuit arrangement for implementing the control arrangement illustrated in  FIG. 4 ; and  
         [0012]     FIGS.  6 ,  7 A- 7 D, and  8  are portions of a schematic diagram depicting another example circuit arrangement for implementing the control arrangement illustrated in  FIG. 4 . 
     
    
       [0013]     The invention is amenable to various modifications and alternative forms. Specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the invention to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.  
       DETAILED DESCRIPTION  
       [0014]     The present invention is believed to be applicable to a variety of model railroad systems. The invention has been found to be particularly advantageous in environments in which it is desirable to operate a model train under a variety of rail conditions. An appreciation of various aspects of the invention can be gained through a discussion of various application examples operating in such environments.  
         [0015]     According to one embodiment of the present invention, a control arrangement receives information from a model train motor regarding the current speed and position of the motor. This information is used to maintain a constant operating speed of the motor over a variety of rail conditions, including, for example, changes in grade. The motor realizes higher torque and efficiency. In addition, jerking and other adverse effects commonly associated with low speed operation of the motor are reduced. Furthermore, an inertial effect can be simulated by continuing to operate the motor for a duration after a main power source is disconnected from the motor. In another particular embodiment of the present invention, two or more motors are disposed on opposite surfaces of a control arrangement. Using multiple motors increases the locomotive power available to the model train.  
         [0016]     In still another particular embodiment of the present invention, the motor speed and position information, as well as information relating to power consumption by the motor, is provided to a sound control system. The sound control system uses this information in selecting sounds to generate, enhancing the realism of the model railroad system and, for many hobbyists, the level of enjoyment.  
         [0017]     Referring now to the drawings,  FIG. 1  depicts a control and motor arrangement installed in a model train  100 . The model train  100  includes a platform  102 , under which a wheeled carriage  104  is mounted to support the model train  100  on a track (not shown). A control and motor arrangement  106  is mounted on a top surface of the platform  102 . The control and motor arrangement  106  includes a control arrangement  108 , which is coupled to control the amount of power supplied to a motor  110 . This motor  110  can be implemented using any of a variety of motor types, including, for example, a DC can-type, ODYSSEY™-type, or PULLMOR™-type motor, commercially available from Lionel LLC of Chesterfield, Mich. Those skilled in the art will recognize that other motor types can be used in the alternative, and that the preceding examples are provided by way of illustration and not limitation. The control arrangement receives from the motor  110  speed information relating to the current rotational speed of the motor  110  and uses this information to adjust the amount of power applied to the motor  110  using a closed feedback loop.  
         [0018]     In addition, the control arrangement  108  optionally further receives from the motor  110  information relating to, for example, the position within the rotational cycle of the motor  110  and/or the amount of power consumed by the motor  110 . This information is used in deciding how much power to apply to the motor  110 . For example, slow rotation of the motor  110  can indicate that the model train  100  is traveling along an upward slope. To compensate for this slope, the control arrangement  108  supplies additional power to the motor  110 . By compensating for variations along the model railroad track, the control arrangement  108  maintains the motor  110  at a constant rotational speed, if the user so desires.  
         [0019]     The control arrangement  108  can also be used to produce other effects that enhance the sense of realism a user enjoys when operating the model train  100 . For example, a real train is significantly affected by inertia. This effect can be observed both when the train starts and stops moving. When a real train starts moving, it does not accelerate to full speed immediately. On the contrary, the train accelerates slowly due to inertia. This effect can be simulated in the model train  100  by applying power to the motor  110  gradually, even when the user commands the model train  100  to assume full speed immediately. Just as a real train typically does not accelerate to full speed instantaneously, it does not, under normal operating conditions, immediately halt when power is removed. Rather, inertia causes the train to continue to move for some time before coming to a halt. This gradual stopping can be simulated in the model train  100  by supplying power to the motor  110  from an alternate power source, such as a battery (not shown), for a time after the primary power source is disconnected from the motor  110 .  
         [0020]     The information provided by the motor  110  to the control arrangement  108  is optionally also provided to other systems in the model train  100 , such as a sound control system. The sound control system can use this information in generating realistic sound effects. For example, if the sound control system receives an indication that the motor  110  is drawing a relatively large amount of power without a correspondingly large increase in speed, the sound control system can fairly conclude that the motor  110  has to work harder to maintain the model train  100  at a constant speed. The sound control system can then select or generate a sound effect that simulates the sound of a train engine straining to drive a train up a hill.  
         [0021]      FIG. 2  illustrates an example control and motor arrangement  200  for use in a model train. A circular base  202  forms a support structure, upon which a rotor  204  is mounted. The rotor  204  rotates about an axis  206  when the control and motor arrangement  200  is energized, driving a motor shaft  208  into rotation about the axis  206 . The motor shaft  208  is supported by a bearing structure comprising spaced apart bearings  210 .  
         [0022]     When the motor is energized, a plurality of windings  212  wound around respective bobbins  214  interact to generate an electromagnetic field within laminar core components  216  and the base  202 . This field interacts with magnets  218  mounted on the rotor  204 , causing the rotor  204  to rotate about the axis  206 . The motor shaft  208  is thus driven into rotation.  FIG. 3  illustrates in plan view one example of a configuration of windings  212  and core components  216 . In the particular example illustrated in  FIG. 3 , a stator winding assembly  300  consists of nine core components  216  and associated bobbins  214  and windings  212 .  
         [0023]     As the motor shaft  208  rotates, a plurality of rotation sensors, one of which is depicted at reference numeral  220 , detect the change in position of the rotor  204 . These rotation sensors  220  can be implemented, for example, using conventional Hall effect detectors. The Hall effect detectors sense voltages produced by changes in the electromagnetic field set up by the windings  212 . In a particular embodiment of the present invention, a plurality of Hall effect detectors, e.g., three, are evenly disposed around the circumference of the control and motor arrangement  200 . With this configuration of rotation sensors  220 , the voltage produced in each rotation sensor  220  varies as a function of the position of the rotor  204  with respect to the base  202 .  
         [0024]     A control circuit arrangement  222  is connected to the motor. The control circuit arrangement  222  receives input from the Hall effect detectors and determines, from the voltages produced in each detector, the position of the rotor  204  in the rotation cycle. In addition, the control circuit arrangement  222  monitors changes in the voltages produced in the detector to infer how quickly the rotor position changes, i.e., the rotational speed of the rotor  204 .  
         [0025]     The control circuit arrangement  222  uses this speed and positional information to determine whether, and to what extent, to alter the amount of power supplied to the motor. For example, if the control circuit arrangement  222  determines that the rotor  204  is rotating slowly for the amount of power supplied to it, the control circuit arrangement  222  can command that more power be supplied to the motor. According to a particular embodiment of the present invention, the speed and positional information is also provided to a sound control arrangement (not shown) to facilitate the generation of sound effects with enhanced realism.  
         [0026]      FIG. 4  illustrates in block diagram form an example control circuit arrangement  400  forming part of a control and motor arrangement, according to another embodiment of the present invention. A power arrangement  402  supplies power to the system. The power arrangement  402  receives power from the model railroad track and also includes a battery circuit to supply power in certain situations, such as when the model train travels over an uneven portion of the track and makes only intermittent contact with the track. Power is supplied to a motor control arrangement  404 , which creates the rotating magnetic field that drives the motor. The power arrangement  402  also provides power to other components of the system, such as a sound control arrangement.  
         [0027]     A radio control interface  406  provides an interface between the control arrangement  400  and a radio controller unit operated by the user. The radio controller unit is used to access various functions, such as speed control, sound effects, and the like. A process control arrangement  408  receives commands from the radio control interface  406  and maintains the speed of the motor at the desired level. For example, if the user commands the model train to run at 40 mph, the process control arrangement  408  maintains the speed at 40 mph, compensating for such factors as upward or downward grades or curves in the track. The process control arrangement  408  also detects faults in the system, such as short circuits. In the event of a short circuit, a short circuit protection arrangement  410  disengages power from the motor when the current flow exceeds a predefined threshold.  
         [0028]     The process control arrangement  408  accesses a memory  412 , which stores certain user-defined information. For example, the user can define a relationship between the rotational speed of the motor and a corresponding speed of the model train. In a particular embodiment of the present invention, the memory  412  is implemented using a nonvolatile memory to facilitate storage of the user-defined information after power is removed from the system.  
         [0029]     A sound information arrangement  414  detects certain operating conditions of the model train and transmits information relating to these conditions to a sound control arrangement (not shown). For example, the sound information arrangement  414  is configured to detect whether the train is traversing a grade and, if so, whether the grade is upward or downward. The sound control arrangement processes this information and selects appropriate sound effects to enhance the sense of realism. For example, if the model train is moving uphill, the process control arrangement  408  senses that more power is required to maintain a constant speed. The process control arrangement  408  thus increases the power supply to the motor. In addition, the sound information arrangement  414  informs the sound control arrangement that more power has been supplied to the motor. The sound control arrangement then selects a sound effect consistent with additional power, such as increased simulated diesel engine noise.  
         [0030]      FIGS. 5A and 5B  illustrate an example circuit arrangement implementing the control arrangement  400  of  FIG. 4 , according to a particular embodiment of the present invention. Primary power is supplied to the circuit from a connection  502  to a rail power supply. A rectifier arrangement  504  converts the AC voltage between the rails to a DC voltage for use by the train. In addition, a connection  506  to a battery serves as an alternate power source when, for example, contact with the rails is interrupted. With the battery serving as a secondary power source, the train maintains operation in the event of such interruptions. A battery circuit  508  conveys power from the battery to the control arrangement  400 .  
         [0031]     A motor controller  510  is responsible for generating the rotating magnetic field that drives the train motor. In the specific embodiment illustrated in  FIGS. 5A and 5B , this magnetic field is generated in three alternating zones. These three zones correspond to three AND gates  512 , each of which receives as input a pulse width modulation signal PWM and a control signal OUTi. The control signals OUTi are provided by a process controller  514 , the operation of which is discussed in detail below. When the control signal OUTi and the pulse width modulation signal PWM are both active for a particular AND gate  512 , power is supplied to a corresponding portion of the motor through a CMOS arrangement  516  and a motor connection  518 . As each portion of the motor receives power in turn, a magnetic field is generated in that portion of the motor. A short circuit protection circuit  520  provides a path to ground in the event of a short circuit. The control signals OUTi are generated by the process controller  514  so as to cause the field to rotate around the motor.  
         [0032]     To generate the control signals OUTi, the process controller  514  monitors the rotational speed of the motor using an input  522  coupled to, for example, a Hall effect sensor. Monitoring the speed of the motor enables the process controller  514  to maintain a constant speed, if desired, over a variety of track conditions. For example, if the process controller  514  senses that the motor is rotating slowly relative to the amount of power supplied to it, it can infer that the train is traveling uphill or over otherwise challenging terrain and apply more power to the motor. Similarly, if the process controller  514  detects that the motor is rotating quickly relative to the amount of power supplied to it, the process controller  514  can decrease the amount of power supplied to the motor to maintain a constant speed. In this manner, the process controller  514  uses speed control closed loop feedback to maintain the motor at a constant operating speed, regardless of track conditions, when desired.  
         [0033]     In addition to the speed of the motor, the process controller  514  optionally receives other inputs that determine the proper amount of power to supply to the motor. For instance, as illustrated in  FIGS. 5A and 513 , the process controller  514  receives information from a user-operated remote control through a radio control interface  524 . This information includes, for example, the desired simulated speed of the train, directional control information, and commands to effect simulation of various sound effects.  
         [0034]     The determination of how much power to supply to the motor depends not only on the input from the remote control and the current speed of the motor, but also on certain user-defined information, such as a mapping between a real-world train speed to be simulated and an actual speed of the model train. In the embodiment illustrated in  FIGS. 5A and 513 , this user-defined information is stored in a non-volatile memory  526 , such as a ROM or an EPROM.  
         [0035]     According to a particular embodiment of the present invention, the process controller  514  outputs speed information to a sound control circuit (not shown) using an output interface  528 . The sound control circuit uses the speed information to determine how to generate or select an appropriate, realistic sound effect. For example, a horn can be programmed to sound relatively quietly when the train is running slowly, but forcefully as the train picks up speed.  
         [0036]      FIGS. 6-8  depict another example circuit arrangement implementing the control arrangement  400  of  FIG. 4 , according to still another embodiment of the present invention. In the circuit arrangement illustrated in  FIGS. 6-8 , prim′ power is supplied to the circuit from a connection  602 , illustrated on  FIG. 8 , to a rail power supply. A full-wave rectifier bridge  604  converts the AC voltage between the rails to a DC voltage for use by the train. In addition, a connection  606  to a battery serves as an alternate power source when contact with the rails is interrupted. The train can thus maintain operation even when such interruptions occur. A battery circuit  608  conveys power from the battery to the control arrangement  400  through a connection  610 .  
         [0037]     To drive the train motor, the control arrangement generates a rotating field. In the specific embodiment illustrated in  FIGS. 6-8 , the magnetic field is generated in three alternating zones, each corresponding to an AND gate  612 . Each AND gate  612  receives as input a pulse width modulation signal PWM and a control signal LOW_ 1 , LOW_ 2 , or LOW_ 3 . These signals are generated by a microprocessor  614 , the operation of which is discussed in further detail below. When the control signal LOW_n (where n is 1, 2, or 3) and the pulse width modulation signal PWM are both active for a particular AND gate  612 , power is supplied to a corresponding portion of the motor using a respective CMOS arrangement  616 . A motor connector  618  provides power to a respective zone of the motor. On  FIG. 6 , the zones are depicted at reference numerals  620 . As each zone of the motor receives power in turn, a magnetic field is generated in that zone. A short circuit protection circuit, depicted at reference numeral  622  on  FIG. 8 , provides a path to ground in the event of a short circuit. The microprocessor  614  generates the control signals LOW_n so as to cause the field to rotate around the motor.  
         [0038]     To generate the control signals LOW_n, the microprocessor  614  monitors the rotational speed of the motor using interfaces ( 624  of  FIG. 6 ) to Hall effect sensors (not shown). A connector  626  connects the interfaces  624  to the microprocessor  614 . By monitoring the motor speed, the microprocessor  614  can use closed loop feedback to adjust the amount of power supplied to the motor in response to changes in motor speed. Thus, the microprocessor  614  can maintain a constant speed over a variety of track conditions, such as changes in grade.  
         [0039]     The microprocessor  614  can also receive other inputs to influence the amount of power to be supplied to the motor. For example, a connection  628  to a control interface enables the hobbyist to provide additional information to the microprocessor  614  using a user-operated radio controller. This information includes, for example, the desired simulated speed of the train, directional control information, and commands to effect simulation of various sound effects. User-defined information, such as a mapping between a real-world train speed to be simulated and an actual speed of the model train, also affects the determination of the amount of power to supply to the motor. In the embodiment illustrated in  FIGS. 6-8 , this user-defined information is stored in a non-volatile memory  630 .  
         [0040]     According to a particular embodiment of the present invention, the microprocessor  614  outputs speed information to a sound control circuit (not shown) using an output interface  632 . The sound control circuit uses the speed information to determine how to generate or select an appropriate, realistic sound effect. For example, a horn can be programmed to sound relatively quietly when the train is moving slowly, but forcefully as the train speed increases. It should be noted that, in the embodiment depicted in  FIGS. 6-8 , either resistor R 106  or resistor R 107  of the output interface  632  is installed. In one embodiment, resistor R 106  is installed to allow direct pin control of audio gain control. As an alternative, resistor R 107  can be installed instead, allowing gating of the PWM signal.  
         [0041]     The various embodiments described above are provided by way of illustration only and should not be construed to limit the invention. Those skilled in the art will readily recognize various modifications and changes that can be made to these embodiments without strictly following the example embodiments and applications illustrated and described herein, and without departing from the true spirit and scope of the present invention, which is set forth in the following claims.