US20080110845A1

US20080110845A1 - Magnetic core actuator

Info

Publication number: US20080110845A1
Application number: US11/598,514
Authority: US
Inventors: Lawrence Dale Edwards; Michael Nathan Dunham
Original assignee: Kadee Quality Products Inc
Current assignee: Kadee Quality Products Inc
Priority date: 2006-11-13
Filing date: 2006-11-13
Publication date: 2008-05-15

Abstract

A magnetic core actuator includes a housing, formed of a non-magnetic material, having a generally tubular shape; a coil, which includes a left hand portion and a right hand portion, wherein each portion, when energized, generates a magnetic field wherein the magnetic fields generated by the left hand portion and the right hand portion have like fields facing one another; and a pair of magnetic armatures, including a left hand armature and a right hand armature, retained in said housing, wherein said magnetic armatures are mounted with like poles facing one another within said housing, said magnetic armatures being driven to opposite ends of said housing by their magnetic fields, and said armatures being shifted towards the center of said housing when power is applied to said coil. As used in a model railroad car, a linkage mechanism extends between the magnetic core actuator and a coupler on a model rail road car for shifting the coupler between its coupled condition and its uncoupled condition.

Description

FIELD OF THE INVENTION

The invention relates to actuators, and specifically to a dual-acting, magnetic core actuator, one application of which relates to a remote uncoupling mechanism for use on model railroad rolling stock.

BACKGROUND OF THE INVENTION

Typical, actuator mechanisms, often times referred to as “solenoids,” include an energizable coil having a metal armature, or core, received therein. The typical core is formed of a non-magnetized, magnetic metal. When the coil is energized, a magnetic field, the actuator, is formed, causing the armature to move relative to the coil. Such relative movement may be linear or circular. Generally, some form of spring-biasing is provided to act on the armature to return it to an at-rest condition when the coil is not energized.
As used for model railroad remote uncoupling applications, a dual-acting actuator is desirable, to operate couplers at both ends of a model railroad rolling stock, i.e., rail cars. Model railroads are constructed to be as close to prototype railroads as possible. To this end, considerable effort is expended in the modelling of engines and rolling stock, which are precise scale models of prototypical railroading equipment. As is to be expected, however, it is not possible to accurately duplicate every feature of a prototypical railroad in a model railroad. Once models are made. considerable effort is made to run model trains as close as possible to their prototypical inspirations. Model railroad clubs have layouts of rather grand scales, provide dispatchers, engineers, yard supervisors and railroad workers, complete with communications equipment, to mimic the operation of a prototypical railroad. While such effort is laudable, and provides a welcome escape from day-to-day life, the operation of the models is still not precisely like the prototype railroads. One of the major problem areas in model railroad operation involves the formation of and the breaking-down of trains, particularly, the coupling and uncoupling of rolling stock units into trains, and the rearrangement of rolling stock within a train.
In a prototype railroad, a conductor is responsible for supervising the addition or removal of cars to a train. This may involve the manual operation of couplers which are located on the ends of cars, or may simply involve the supervision of automated train formation and break-down equipment. In the case of the manual operation, the conductor physically operates the couplers, and signals the engineer when the locomotive, and the cars attached thereto, are to move. Cars may be disconnected from the train at any point along the track, and may be picked up from any point along the track. Model railroads have been limited in train building and breaking because the couplers manufactured for use on model trains, while somewhat prototypical in operation, are not provided with scale conductors to perform the coupling and uncoupling operations along the track.
A variety of coupler types are known for use with model railroads. Some trains are “built” with non-operating couplers, which will remain permanently joined to one another, thereby forming a train with a set number of cars therein, which is always run as a unit. One type of operating coupler is the National Model Railway Association (NMRA) hook-and-horn coupler, which will automatically couple two units of rolling stock together when the couplers on the rolling stock units are pushed into one another, either manually, or by a model locomotive. Special uncoupling ramps must be provided to uncouple these couplers, which ramp includes an insert, which is located between the rails of model railroad track, and a pair of spaced apart wires, which extend above the insert and which will serve to uncouple two units of rolling stock when the couplers on the rolling stock are backed through the wires. The NMRA hook-and-horn coupler, and its associated uncoupling ramp, is not prototypical, and detracts from the realism of model railroad operation.
Another type of coupler which is used in model railroad rolling stock is the Magne-Matic® coupler which is manufactured by Kadee Quality Products Company, e.g., U.S. Pat. No. 5,785,192, granted Jul. 28, 1998 to Dunham et al., for Improved model railroad coupler. The Magne-Matic® coupler closely resembles a prototypical coupler in that it is able to be remotely coupled and uncoupled. Known uncoupling devices for the Magne-Matic® coupler include an uncoupling ramp, which is a bar magnet, and which may be placed in between the rails of the model railroad track. Alternately, an electromagnetic uncoupling ramp may be placed beneath the support for the track, which will enable an operator to remotely uncouple rolling stock which is located over the uncoupling ramp. A number of other companies make couplers similar to the Magne-Matic® coupler, which provide varying degrees of performance.
Even in the case of the Magne-Matic® coupler, a model railroader is limited as to where uncoupling may take place, in that a fully automatic uncoupling operation may occur only over an uncoupling ramp. A number of hand-held devices are available which enable an operator to manually uncouple rolling stock by inserting a pair of spaced-apart, opposed magnets between two pieces of rolling stock, which magnets will cause the Magne-Matic® couplers to uncouple. This may be realistic in the sense that prototypical railroads require human intervention to uncouple the cars, however, in the case of model railroads, the presence of a “giant conductor” on the layout is not prototypical. In many instances, it may be desired to uncouple cars in an area that is not easily reachable by a model railroader, or in one which does not have an uncoupling ramp or electromagnetic uncoupling activator. One form of remote uncoupler is described in U.S. Pat. No. 5,775,524 to Dunham, for Remote uncoupling mechanism.

SUMMARY OF THE INVENTION

A magnetic core actuator includes a housing, formed of a non-magnetic material, having a generally tubular shape. A coil, which includes a left hand portion and a right hand portion, is formed on the housing, wherein each coil portion is wound in an opposite direction about the housing, and wherein a cross-over lead extends between the coil left hand portion and the right hand portion. When energized, the coil generates a magnetic field from each coil portion, the magnetic fields having opposed poles along the length of the housing. A pair of magnetic armatures, including a left hand armature and a right hand armature, are retained in the housing, wherein said magnetic armatures are mounted with like poles facing one another within the housing. The magnetic armatures are driven to opposite ends of the housing by their magnetic fields, and the armatures are shifted towards the center of the housing when power is applied to the coil.
A model railroad remote uncoupling mechanism is intended for use with a signal-receiving mechanism and a self-centering coupler, wherein the coupler is mounted on a model railroad car, and is shiftable between a coupled condition, wherein the coupler engages a coupler on another model railroad car, and an uncoupled condition, the remote uncoupling mechanism including a magnetic core housing which is activated by the signal-receiving mechanism; said magnetic core housing, a linkage mechanism extends between the magnetic core actuator and the coupler for shifting the coupler between its coupled condition and its uncoupled condition.
It is an object of the invention to provide a dual-acting actuator.
Another object of the invention is to provide a dual-acting actuator which does not require spring biasing to return the armatures thereof to an at-rest condition.
It is an object of the invention to provide a model railroad remote uncoupler mechanism which may be used at any position on a model railroad layout.
Another object of the invention is to provide a remote uncoupler mechanism which is usable with existing model railroad couplers.
A further object of the invention is to provide a remote uncoupler mechanism which may be retro-fitted into existing pieces of rolling stock.
Yet another object of the invention is to provide a remote uncoupler mechanism which provides realistic operation of a coupler mounted on a model railroad rolling stock.
Another object of the invention is to provide a remote uncoupling mechanism which operates at low voltages, such as that provided on a model railroad track.
This summary and objectives of the invention are provided to enable quick comprehension of the nature of the invention. A more thorough understanding of the invention may be obtained by reference to the following detailed description of the preferred embodiment of the invention in connection with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a somewhat schematic side elevation of a model railroad rolling stock have a remote uncoupling mechanism which incorporates the magnetic core housing of the invention.

FIG. 2 is an enlarged side elevation of the magnetic core actuator of the invention.

FIG. 3 is an enlarged schematic of the magnetic core actuator in a non-energized condition.

FIG. 4 is an enlarged schematic of the magnetic core actuator in an energized condition.

FIG. 5 is a top plan view of a coupler in a coupled condition.

FIG. 6 is a top plan view of a coupler in an uncoupled condition.

FIG. 7 is a bottom left perspective view depicting connection of a linkage mechanism to a coupler.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A magnetic core, dual-acting actuator is fabricated in a small size and requires minimal power, while still retaining force sufficient to actuate an uncoupling mechanism. The magnetic core, dual-acting actuator will be described in conjunction with a remote uncoupling mechanism for a model railroad car. Referring now to FIG. 1, a model railroad car is shown in side elevation generally at 10, with a body 12 thereof shown in phantom to show internal details. A remote uncoupling mechanism 14 includes a magnetic core, dual-acting actuator 16 constructed according to the invention. A power supply 18 provides power to actuator 16 and to a digital command and control (DCC) receiver, or controller, 20. Uncoupling mechanism 14, power supply 18 and DCC controller 20 are all mounted on a undercarriage 22 of car 10. DCC controller 20, while used as an example herein, may be replaced by other signal-receiving and signal generating devices, which may be activated by an RF or infrared signal, and which are operable to activate actuator 16.
Referring now to FIGS. 2-4, actuator 16 includes a coil 24, which is arranged in a linear fashion, and includes a left hand portion 26 and right hand portion 28, each wound in an opposite direction about an actuator housing 30, such that, when energized, coil 24 produces two magnetic fields having opposing polarities. As shown in FIG. 4, the coils have like-magnetic polarities facing one another. Housing 30 includes a pair of coil retainers, or bobbins, 32, and is formed of non-magnetic material, formed into a tube, having, in the preferred embodiment, crimped ends 34. Thus, housing 30 may be formed of a non-ferrous metal, or from some form of substantially rigid polymer. Retainers 32 may be integrally formed with housing 30, or may be formed separately, and fitted on housing 30. As depicted in FIGS. 3 and 4, housing 30 includes integrally formed bobbins 32. In some embodiments, bobbins 32 may be formed in a spaced apart configuration without a “housing” per se. As used herein, “housing” is any structure with or without integrally formed or fitted bobbins, which position armatures 36, 38 in an operable fashion.
A pair of magnetic armatures, including a left hand armature 36 and a right hand armature 38, are retained in housing 30, as depicted in FIGS. 3 and 4, with magnetic armatures 36, 38 being mounted with like poles facing one another within housing 30. Each armature may be encased in a thin-walled sleeve, 36S, 38S, which provides an attachment point for other components of uncoupler mechanism 14. Alternately, any attachment device which allows attachment of a linkage mechanism to an armature and to a coupler is sufficient. Sleeves 36S and 38S are formed of a non-ferrous metal, e.g., brass, or of a polymer material, so long at the sleeve provides a clearance, movable fit within housing 30, and does not increase the friction between armatures 36, 38 and housing 30. Thus, when at rest, when coil 24 is not energized, magnetic armatures 36, 38 tend to urge each other to the distal portions of the housing. This magnetic opposition acts as an invisible “compression spring,” forcing left hand armature 36 and right hand armature 38 away from each other when coil 24 is in a non-energized state. Both right hand and left hand armatures are restrained from traveling outside of their maximum extended position, which maximum extended position is determined by various operating parameters. It is imperative that left hand armature 36 and right hand armature 38 not travel so far in their respective extended positions as to allow their magnetic poles to extend beyond the magnetic field generated by coil 24 when energized. Armatures 36, 38 are selected of suitable magnetic material and sized, along with housing 30, to exert an adequate force on each other so as to travel to opposite ends of housing 30, yet to exert an opposing magnetic force which is sufficiently weak as to be easily overcome when coil 24 is energized.
Power is supplied to coil portions 26, 28 by leads 40, 42 from DCC controller 20. The leads of the coil portions' end windings are connected by a cross-over lead 44. When energized, coil 24 produces dual magnetic fields, having opposing polarities with like magnetic poles thereof facing one another, which act on magnetic armatures 36, 38. When coil 24 is energized, the armatures' magnetic fields react to the to the coils' magnetic fields, forcing the armatures to the center of their related coil portions' magnetic field and towards the center of housing 30 (arrows 46, FIG. 4), until such time that current is removed from the coil and the armatures move away from each other as a result of their own opposing magnetic field. Referring to FIG. 4, when coil 24 is energized with DC, left hand coil portion 26 generates a magnetic field as shown wherein coil portion 26 has a north magnetic pole adjacent armature 36 south magnetic pole, thereby drawing armature 36 to the center of the magnetic field generated by coil portion 26 and towards the center of housing 30. Likewise, right hand coil portion 28 acts in a similar fashion on armature 38. When current is removed from coil 24, the electromagnetic fields of the coil collapse, and the armatures repulse each other, returning to their at-rest conditions adjacent the distal ends of housing 30.
Power supply 18 may be an internal battery, or may include pickups which draw power from the rails on which the car travels. In the case of a battery mounted within car 10, batteries such as plural AAA batteries, or a single 9V battery, may be provided. The batteries provide sufficient voltage and current to operate DCC receiver 20 and actuator 16 for a reasonable period of time.
Pickups which draw power from the energized rails are well known to model railroaders and may be accomplished in a number of ways. One such way is to provide a truck having an electrically conductive wheel on one end of an electrically conductive axle, with the wheel on the other end of the axle either being insulated or being formed of a plastomer material. The truck side frame members may be formed of a plastomer material, or may be insulated from the axle. The second axle on the truck is configured as the first, however the metallic wheel is located on the other side of the truck. Pickup brushes may be placed in contact with the axles and connected to power supply.
Referring to all of the drawing figures, model railroad remote uncoupler mechanism 14 is constructed according to the invention. Uncoupler mechanism 14 is mounted in car 10, which includes undercarriage 22, body 12, and a pair of trucks 48, 50, located adjacent each end of undercarriage 22. Trucks 48 and 50 each include a side frame 52, a bolster 54 extending between spaced-apart sides 52, springs 56 and wheels 58 which are mounted on axles.
Trucks 48 and 50 are mounted to undercarriage by means of truck mounts, which may take the form of the mounts described in U.S. Pat. No. 5,090,332, granted Feb. 25, 1992, to Edwards et al., for Self-Centering Model Railroad Truck. Car 10 moves on spaced apart rails, which rails may be energized by an electric current.
Uncoupler mechanism 14 includes actuator 16 which is connected to couplers 58, 60, located on each end of car 10 by a linkage mechanism 62. Linkage mechanism 62 includes a connecting arm 64, which may extend along the upper surface of undercarriage 22, and passes through a connector passage in body 12 (not shown) to a connecting wire, or coupler linkage, 66, fixed to a knuckle 68 of coupler 58. Connecting arm 64 may also be constructed and arranged to pass through an opening in undercarriage 22, and extend along the lower surface of the undercarriage.
Couplers 58, 60 are of the well-known Magne-Matic® coupler type, which are self-centering couplers, and which include a coupler shank 70, received in a draught box (not shown) mounted on the underside of undercarriage 22. At the free end of shank 70, a coupler head 72 is formed, which includes coupler knuckle 68, which is swingable between a coupled, centered condition (FIG. 5) and an uncoupled, off-center condition (FIG. 6). Couplers 58, 60 are biased to their centered condition by a spring mechanism which act on the draught box. Coupler knuckle 68 is biased to its coupled condition by a spring 74. Details of couplers 58, 60 may be found in, e.g., U.S. Pat. No. 5,785,192.
Linkage mechanism 62 is operable to shift a coupler between its coupled condition, as depicted in FIG. 5, and an uncoupled condition, depicted in FIG. 6. As shown in FIGS. 5 and 6, connecting arm 64 has an elongate receiver 76 therein, which receives connecting wire 66, and which allows free travel of connecting wire 66 therein so that couplers may continue to act in response to well-known magnetic uncoupling devices of various types, which act on an “airhose” trip pin 78, which is formed of a magnetically-responsive metal.
FIG. 7 depicts an alternate embodiment of the connecting are and coupler linkage, including a connecting arm 80, which passes through undercarriage 22 at some location between the actuator and the coupler, and is slidably received in a coupler arm 82. Coupler arm 82 includes a transverse portion 84 and a trip-pin receiver portion 86. Transverse portion 84 includes a bore 88 therein for receiving connecting arm 80, and which is constructed and arranged so that connecting arm 80 is slidable in bore 88, which allows the coupler to be activated by traditional magnetic activation or by activation of the actuator. Coupler arm 82 may be formed of wire, or molded plastic or non-ferrous metal. Coupler arm 82 may be snug fitted to trip pin 78, and closely resembles a portion of a prototypical uncoupling linkage. The provision of coupler arm 82 further facilitate retrofit of the uncoupling mechanism of the invention into existing model railroad cars because there is no need to install a coupler which is specific to the uncoupling mechanism.
DCC controller 20 serves as a signal-receiving mechanism, and is attached to power supply 16. Upon receipt of a RF signal, the signal-receiving mechanism generates a trigger signal, which trigger signal causes actuator 16 to be powered, thereby moving linkage mechanism 62, thus moving the coupler(s) to their uncoupled conditions. Upon termination of the signal, power is shut off to actuator 16, which returns to an at-rest condition, allowing the couplers attached thereto return to their coupled conditions.
The actuator of the invention may be applied to other tasks, particularly on model railroad layouts, such as activating turnouts, operating moving scenic and aesthetic features on the layout, etc. A modified form of the actuator of the invention has a single armature received within a coil, and is particularly useful as a switch motor.
Thus, a dual-acting, magnetic core actuator, and a use of the actuator in a remote uncoupling mechanism for use in a model railroad car, has been disclosed. It will be appreciated that further variations and modifications thereof may be made within the scope of the invention as defined in the appended claims.

Claims

1. A magnetic core actuator comprising:

a housing, formed of a non-magnetic material, having a generally tubular shape;

a coil, which includes a left hand portion and a right hand portion, wherein each portion, when energized, generates a magnetic field wherein the magnetic fields generated by the left hand portion and the right hand portion have like fields facing one another;

a pair of magnetic armatures, including a left hand armature and a right hand armature, retained in said housing, wherein said magnetic armatures are mounted with like poles facing one another within said housing, said magnetic armatures being driven to opposite ends of said housing by their magnetic fields, and said armatures being shifted towards the center of said housing when power is applied to said coil.

2. The magnetic core actuator of claim 1 wherein each coil portion is wound in an opposite direction about said housing, and wherein a cross-over lead extends between said coil left hand portion and said right hand portion, said coil, when energized, generates a magnetic field from each coil portion, said magnetic fields having opposing poles along the length of said housing.

3. The magnetic core actuator of claim 1 wherein said housing includes a pair of coil retainers which retain each coil portion therein.

4. The magnetic core actuator of claim 1 which is mounted in a model railroad car and which is connected to a linkage mechanism, a controller and a power supply, for remotely uncoupling the model railroad car from another like model railroad car upon receipt of a signal by said controller.

5. The magnetic core actuator of claim 4 which is activated by a signal-receiving mechanism, and which is connected by a linkage mechanism to a self-centering coupler, wherein the coupler is mounted on a model railroad car, and is shiftable between a coupled condition, wherein the coupler engages a coupler on another model railroad car, and an uncoupled condition, wherein said linkage mechanism extends between the magnetic core actuator and the coupler for shifting the coupler between its coupled condition, when the coil is not energized, and its uncoupled condition, when the coil is energized.

6. The magnetic core actuator of claim 4 wherein said linkage mechanism includes a connecting arm connected, at one end thereof, to a magnetic core actuator, which connecting arm other end is connected to a coupler knuckle.

7. The magnetic core actuator of claim 6 which includes a coupler arm fixed to said coupler knuckle.

8. The magnetic core actuator of claim 7 wherein said coupler arm is connected to a coupler trip pin.

9. The magnetic core actuator of claim 4 which further includes a power supply for said magnetic core actuator.

10. The magnetic core actuator of claim 9 wherein said power supply is carried on-board the rolling stock.

11. The magnetic core actuator of claim 9 wherein said power supply comprises power supplied to spaced-apart rails on which the model railroad car rolls, and which includes a pickup mechanism for transferring power from the rails to said magnetic core actuator.

12. A model railroad remote uncoupling mechanism for use with a signal-receiving mechanism and a self-centering coupler, wherein the coupler is mounted on a model railroad car, and is shiftable between a coupled condition, wherein the coupler engages a coupler on another model railroad car, and an uncoupled condition, comprising:

a magnetic core actuator which is activated by the signal-receiving mechanism; said magnetic core actuator comprising:

a housing, formed of a non-magnetic material, having a generally tubular shape;

a coil, which includes a left hand portion and a right hand portion, wherein each portion, when energized, generates a magnetic field wherein the magnetic fields generated by the left hand portion and the right hand portion have like fields facing one another; and

a pair of magnetic armatures, including a left hand armature and a right hand armature, retained in said housing, wherein said magnetic armatures are mounted with like poles facing one another within said housing, said magnetic armatures being driven to opposite ends of said housing by their magnetic fields, and said armatures being shifted towards the center of said housing when power is applied to said coil; and

a linkage mechanism extending between the magnetic core actuator and the coupler for shifting the coupler between its coupled condition and its uncoupled condition.

13. The magnetic core actuator of claim 12 wherein each coil portion is wound in an opposite direction about said housing, and wherein a cross-over lead extends between said coil left hand portion and said right hand portion, said coil, when energized, generates a magnetic field from each coil portion, said magnetic fields having opposing poles along the length of said housing.

14. The uncoupling mechanism of claim 13 which further includes a power supply for said magnetic core actuator.

15. The uncoupling mechanism of claim 12 wherein said power supply is carried on-board the rolling stock.

16. The uncoupling mechanism of claim 12 wherein said power supply comprises power supplied to spaced-apart rails on which the model railroad car rolls, and which includes a pickup mechanism for transferring power from the rails to said magnetic core actuator.

17. The uncoupling mechanism of claim 12 wherein said linkage mechanism includes a connecting arm connected, at one end thereof, to a magnetic core actuator, which connecting arm other end is connected to a coupler knuckle, which further includes a coupler arm fixed to said coupler knuckle trip pin.

18. The uncoupling mechanism of claim 12 which is activated by a signal-receiving mechanism, and which is connected by a linkage mechanism to a self-centering coupler, wherein the coupler is mounted on a model railroad car, and is shiftable between a coupled condition, wherein the coupler engages a coupler on another model railroad car, and an uncoupled condition, wherein said linkage mechanism extends between the magnetic core actuator and the coupler for shifting the coupler between its coupled condition and its uncoupled condition.