US2084257A - Track shoe and shunting circuit - Google Patents

Description

June 15, 1937. EDMN A 2,084,257

TRACK SHOE AND SHUNTING CIRCUIT Original Filed Dec. 7, 1932 3 Sheets-Sheet 1 A.C.O .C. POWE INVENTOR. J o SEPH LEDWINKA.

ATTORNEY.

June 15,, 1937. J. LEDWINKA TRACK SHOE AND SHUNTING CIRCUIT 3 Sheets-Sheet 2 Original Fil ed Dec. 7) 1932 1 3. INVENTOR. JOSEPH Lzowmwa.

BY n

ATTORNEY.

June 15, 1937.

J. LEDWINKA TRACK SHOE AND SHUNTING CIRCUIT Original Filed De. '7, 1932 3 Sheets-Sheet 3 INVENTOR. I o SEPH LEDWINKA.

, ATTORNEY.

Patented June 15, 1937 UNITE STAS TRACK SHOE AND SHUNTING CIRCUIT vania Application December 7, 1932, Serial No. 646,104 Renewed November 16, 1936 11 Claims.

This invention relates to railway signalling and more particularly to the method and means for the shunting of railway signalling track circuits.

The present invention relates to the shunting of track circuits by rail vehicles, and has for its principal object the shunting of such circuits by single car trains or pneumatic tired rail vehicles.

The maintenance of adequate shunts on track circuits has always been an important, if not vital question in the design of railway signal apparatus, and with the development of single unit selfpropelled rail vehicles of recent years, the problem has been greatly accentuated. Due to the light weight of the vehicles, the necessary breaking down of the scale film on track rails has been diificult, if not frequently impossible. Again, where the weightis substantially that of but single unit vehicles, for instance, in the case of deadhead locomotives traveling over the tracks, if the speed of the unit is relatively high, the passage over short sections of track which operate crossing signals has been so rapid as to, on occasion, result in either the non-operation of a crossing signal or upon other occasions to have resulted in the improper operation of the crossing signals as well as their partial operation. I

Where the light-weight rail cars have steel wheels and axles, a shunting path between the rails is provided if the contact resistance between the rails and the wheels is sufficiently low. The only known method of insuring this operation or this low contact resistance was by means of increasing the weight per wheel. However, where it is desirable to reduce the weight of the car itself, it is natural that the increase of weight on the wheels is contrary to the fundamental principles of light weight rail car design. Under these conditions track circuit operation was not entirely satisfactory, and railroads have found it necessary to promulgate special orders concerning the operation of such vehicles.

The introduction of pneumatic tired rail vehicles into operation on many of the railroads has made it imperative that new methods and apparatus for shunting the railway signalling track circuits be introduced which do not depend upon the weight of the car or the weight per wheel to reduce the shunt resistance sufiiciently low to operate the signal circuits. As pneumatic tired rail vehicles insulate the wheels and axles from the tracks, it is vitally essential that some contact -mechanism be developed. This, applicant has accomplished, by the provision of brushes or shoes which contact with the rails, making suitable connections between the (Cl. l9145) rails and providing rail to rail shunts carried upon the vehicle. Necessarily, if the full advantages of the pneumatic or rubber tired vehicles are to be utilized, substantially none of the vehicle weight can be carried upon the rail engaging shoes. As a necessary result of this, much more unreliable operation of track signal circuits will result. To overcome these diflicult problems, the apparatus herein disclosed has been developed.

Another object of this invention is the construction of a satisfactory rail engaging member which may be a setaceous contact of the brush typewhich will not be subject to undue wear in operation, and which will be readily susceptible of economical replacement of parts when the wear of actual usage becomes sufficient for this replacement to be necessary.

Another object of this invention is to accomplish the shunting of track circuits by means of the interposition of a plurality of conducting paths between the track rails independently of the vehicle wheels and axles.

Another object is to accomplish this track circuit shunting by means of conducting paths interposed between the track rails having track contacting elements interconnected in staggered relation so as toinsure a proper signalling operation if the insulating rail joints of the signal blocks are not directly opposite each other but are rather staggered as to the rail sections.

Other objects will be readily apparent by a reading of the specification and sub-joined claims in connection with the accompanying drawings, among which might be mentioned the construction of the shoes in such a manner as to break down any substantially non-conducting surfaces on the track rails, such as scale, rust, etc., and to break down any such similar surfaces, for instance, ice on the rails.

This invention will be better understood from a consideration of the accompanying drawings, wherein like ordinals represent corresponding parts in the various figures.

Figure 1 is a truck of a pneumatic tired rail vehicle showing a plurality of brushes mounted at one side of the truck upon a supplemental framework.

Figure 2 is an enlarged side elevation of the track engaging shoe or setaceous contact element or brush, and its supporting structure.

Figure 3 is a section on the line 3--3 of Figure 2 showing the portions of the supporting framework and the track shoe in section.

Figure 4 is an enlarged detail section through the track shoe.

Figure 5 is a simplified circuit diagram of the system as applied to a single unit rail vehicle.

Referring to the various figures of the drawings in more detail, in Figure 1 is shown a vehicle truck l having pneumatic tired wheels I! of suitable form. Mounted upon this truck is a power means l2 which may comprise some prime mover of suitable form, for instance, an internal combustion engine. Upon a supplemental framework l3 upon the side of the vehicle truck are supported the track engaging brushes or contacts l4. The brushes I4 are shown in tilted position corresponding to the position assumed when the vehicle is in motion in the direction of the arrow. The vehicle truck ill, the wheels l5 and the hub or axle end plates iii are necessarily insulated from the track rails ll due to the interposition of the pneumatic tires H between the rails IT and the metallic wheels i5. The brush supporting structure I3 is likewise insulated from the rails due to the interposition of an insulating member l8 between the two parts of the shoe in such manner as to insulate them from each other. As a result of the insulated relation between the track rails and the various parts of the vehicles, axles, Wheels, etc, it is quite obvious that a shunt between the rails is not available. To sufiiciently reduce the resistance of the track circuit so as to operate the signals, additional mechanism must be available for creating a shunt.

This is provided by connecting low resistance contacting paths between the brushes at opposite sides of the vehicle. This connection may be made by means of leads l9 secured to a terminal connection 20.

As seen in Figure 2, the contact member is so constructed. as to readily tilt about the pivot 2| located centrally of the head portion 22 of the shoe. To provide limiting elements allowing the brush to tilt in a direction through a limited radius, a plurality of limit stops 23 are provided to limit this motion. The limit stops are so constructed with relation to the pivoting action of the head that the contacting surfaces of each of the metallic bristle members 24 are in substantially a plane parallel with the surface of the track rails. This plane is also tangential to an are using the pivot point as the center. Other modifications of the head construction are readily apparent, for instance, the head portion may be constructed in the central area somewhat of a box-like construction, the end walls of the box providing limit stop areas for the tilting motion.

The supplemental framework 13 consists of a plurality of column members 25 and 26. A connecting plate 2'! is secured to these column members by welding or some other means, and to these plates are secured a plurality of base plates 25. Upon the base plates are provided a plurality of cone-shaped bracket members 29, preferably hollow in section so as to provide suilicient strength but also light weight. At the outer extremity of the brackets are pivotally mounted rollers 38 having channel shaped grooves in their peripheries providing for reception of the vertical member 3| which is secured to the shoe. These brackets and rollers are mounted at each side of the vertical member 3| so that this member is free to ride up and down within the slot provided. Vertical motion is limited by means of a pin 32 which is adjustable to various positions and which prevents the brush from dropping out of its supporting structure. For the purpose of keeping these pivot bearings clean, and in good operative order, the shroud or cover plate 33 is provided, the opposite sides of which are arcuate in contour, providing sufficient clearance between the wheels. The shoe M at the pivotal connection is secured to the vertical member 3| by means of a bifurcated yoke 34 which in turn is secured to the hollow vertical shaft 3| by means of a pin 2| which secures the hollow box-like member to the stub head of the yoke 34.

The construction thus far described provides a light weight simplified mechanism whereby the brushes will, at all times, cooperate in contacting relation with the rail surface, and in slight variation in track levels or motion of the car body will be compensated for by the combined sliding and roller bearing type of connection between the vertical member and its cooperating peripheries of the rollers.

For the purpose of economical replacement of the bristles, if wear becomes excessive they may be constructed as shown. in Figure 4, comprising U-shaped members, two bristle like portions of which pass through separate holes in the base portion 35 of the shoe. It is quite obvious that it is not necessary that these U-shaped members pass through apertures 36, in stepped relation, but that they could be just as readily made to pass through adjacent apertures in the same elevational plane.

Another ready modification of this construction would be having each bristle individual unto itself and having an enlarged head portion upon it so that the same would seat within the enlarged countersunk opening 31 of the holes, in the base portion. Any suitable insulating material may be used as may be desirable.

Referring to Fig. 5 of the drawings, several methods of interconnecting the shoes are illustrated, For instance, the corresponding leads and terminals I9 and 20 respectively of directly opposite brushes 4!! and 4! may be connected by means of the connecting leads 42 and 43. next set of brushes 44 and 45 may likewise be connected by leads 46 and 41. A similar connection of the brushes at the opposite end of der some circumstances, however, it is desirable that the conducting paths at opposite endsof the vehicle be connected so that for the operation, for instance, of grade crossing signals absolute certainty of operation is insured. Under these circumstances, the leading brushes and/or sets of brushes 5!! and 5| may be connected by means of a conducting path between the terminals A-A or the leading and trailing contact or sets of contact elements may be interconnected by,

a conducting path between the terminals AB. Either system is satisfactory and operative, being equally satisfactory on either A-C or DC signalling circuit systems.

It is readily apparent that other satisfactory connections may be made and it is obvious that the constructions shown are merely one emboditrue spirit and scope of this inventive concept as revealed in the appended claims.

What I claim is:

1. A rail engaging shoe comprising a plurality of V-shaped plate members in secured insulated relation, one of said members carrying a plurality of track engaging current conducting elements removably secured therein, and a vertically extending and vertically reciprocable supporting arm the other of said members being pivotally connected to said supporting arm.

2. A rail engaging brush mechanism comprising a vertically yieldable member and a V-shaped current conducting tiltable brush pivotally secured thereto, said brush including limit stops to predetermine said tilting motion with respect to said vertical yieldable member in accordance with the angle of the V.

3. A track contact mechanism comprising a vertically extending and vertically movable arm,

a tiltable current conducting track brush pivotal- 1y secured to said arm, a plurality of roller members constituting roller slide bearings for said vertical arm, and a housing for said mechanism.

4. A tiltable track contact shoe comprising a head portion, a pivot centrally of said portion, stops on said head portion to limit tilting of said shoe in trailing position as to car motion about said pivot, a base portion in secured spaced re- 30 lation to said head portion, an insulating member interposed between said portions, and a pinrality of conducting metallic bristle-like members forming track contacting surfaces, said bristle-like members being connected to and ex- 35 tending from said base portion.

5. A tiltable track contact shoe comprising a head portion, a pivot centrally of said portion, stops on said head portion to limit tilting of said shoe in trailing position as to car motion about said pivot, a base portion in secured spaced relation to said head portion, said head and base portions being complementally V-shaped, an insulating member interposed between said portions, and a plurality of conducting metallic bristle-like members forming track contacting surfaces substantially parallel to the sides of said V-members, said bristle-like members being connected to and extending from, said base portion.

6. A track contacting signal shoe for rail vehicles comprising head and base members, an insulating member interposed between said members, the base member having a plurality of stepped rows of openings, and metallic track contacting current conducting members extending through said openings, and together forming substantially V-shaped surfaces.

7. Trolley contact mechanism for vehicles comprising a support rectilinearly reciprocal on a line transverse to the path of travel of the vehicle, a V-shaped contact device pivoted to the support within the angle of the V, whereby either of the arms of the V are adapted to ride in contact with a. trolley conductor and conduct current therefrom, and positive limit stops between the support and the V-shaped contact limiting the oscillation of the \/-shaped contact to an angle the complement of the angle of the V.

8. A trolley contact mechanism for vehicles comprising a supporting arm vertically reciprccable upon the vehicle, and a V-shaped trolley contact pivotally connected with the arm within the angle of the V adapted to be oscillated on its pivot to bear with either arm upon a trolley conductor and conduct current therefrom, the combined weight of the support and the brush being such as to constitute the sole bias of the contact to the conductor and effect the shift of contact from one arm of the V to the other in accordance with change of direction of motion of the vehicle.

9. Trolley contact mechanism for vehicles comprising a supporting arm and a V-shaped trolley contact pivoted to said arm to be shifted in accordance with the direction of motion of the vehicle to engage the trolley conductor through one arm of the V or the other, and current conducting bristles projecting from the faces of the arms substantially parallel to the bisector of the angle of the V, whereby the bristles trail from that branch of the V which contacts with the rail.

10. A trolley contact mechanism for vehicles comprising a supporting arm rectilinearly reciprocable toward and from a trolley conductor on a line substantially at right angles to the travel of the vehicle, a V-shaped trolley contact pivoted to said arm and adapted to contact with the trolley conductor through either branch of the V in accordance with the direction of movement of the vehicle and conduct current therefrom, said arm and contact having means urging them into engagement with the trolley conductor and constituting as such the sole means biasing contact on its pivot in accordance with the direction of motion of the vehicle.

11. In a trolley contact mechanism, a current conducting contact brush having a mounting head portion and a base portion, insulating material between the two portions and bristles threaded through the base portion and having heads confined upon said base and withheld from contact with said head portion by said insulating material.

JOSEPH LEDWINKA.

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