US1442684A - Interlocking system for railroads - Google Patents

Description

Jan. 16, 1923.

E. C. LARRY. INTERLOCKING SYSTEM FOR RAILROADS.

I FILED JUNE 4, I920.

3 SHEETSSHEE1 1.

V 1,442,684,. E, C. LARRY. INTERLUCKING SYSTEM FOR RAILROADS. FILED JUNE 4, 1920 3 SHEETSSHEET 2.

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Jan; 16, 1923p E, C LARRY! INTEBLDGKING STEM FOB BA LRQ DS.

FILED JUNE h 1820: HEET5 H 3' Fl a.

Patented Jan. 16, 1923.

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UNETEO STATES PATENT OFHQE.

EDWIN C. LARRY, OF ROCHESTER, NEW YORK, ASISIGNOR TO GENERAL RAILVTAY SIGNAL COMPANY OF ROCHESTER, NEW YORK, A CORPORATION OF NEW YORK.

INTERLOCKING SYSTEM FOR RAILROADS.

Application filed June 4, 1920.

To all whom it may concern:

Be it known that I, EDWIN'C. LARRY, citizen of the United States, residing at Rochester, in the county of Monroe and State of New York, have invented certain new and useful Improvements in lnterlocking Systems for Railroads, of which the following is a specification.

This invention relates to interlocking sys tems for railroac s. v

lVhen the switches, signals, and other functions are few in number and comparatively close together, they may be satisfactorily operated mechanically, but where there are one or more functions at a distance from the tower, it is desirable to operate these by power, and in order to retain the same kind of interlocking between the levers, it is preferable to control these power operated functions by a mechanical. lever. The present invention relates more particularly to a construction and arrangement of parts and circuits suitable for incorporation with a mechanical lever so as to permit the safe and reliable operation of switches or other functions at a distance from the tower. The invention further contemplates the use of alternating current as the source of power for operating these distant functions, and the devices associated with the lever, particularly the indication mechanism, are constructed and adapted for use with such alternating current.

Other features and advantages of the invention will appear hereinafter.

In describing the invention in detail reference will be made to the accompanying drawings in which:

Figure 1 is a general view of a mechanical lever of well known construction, showing the application thereto of an electric lock or indication mechanism embodying the in vention;

Fig. 2 is a longitudinal section through the electric lock;

Fig. 3 is a transverse section through the lock taken on the line 3-3 in Fig. 2;

Fig. 4 is afragmentary horizontal section taken substantially on the line 44 in Fig. 2;

Figs. 5, 6 and 7 are detail views showing the position of the parts during different stages of the operation of the electric lock; and i Fig. 8 is a diagrammatic view in the Serial No. 386,464.

nature of a circuit diagram showing the circuit connections of a system embodying the invention.

Fig. 1 shows one lever of the well known naxby and Farmer interlocking machine, with the improvement constituting the present invention applied thereto. The lever L is fastened to a shoe 1 which is mounted on a pin 2 supported by the bottom girder 3 of the machine in the usual way. A latch handle t is pivoted on the lever L and is connected by a rod 5 to a rocker die 6, which is pressed down by a spring 7. The die 6 engages with shoulders 88 on the fixed quadrant, and the die slides in a curved slot 9 in the rocker 10 pivotally supported at its middle on a pin 11. The rocker 10 is connected by a link 12 to the locking shaft 13 which actuates the mechanical interlocking of the machine in the usual way, said interlocking being supported upon the bed 14.

The electric lock or indication mechanism M embodying this invention is supported above the locking bed 14 in a suitable manner, and is connected by a rod 15, having an adjustable clevis at its lower end, to the rocker 10. The indication mechanism M prevents movement of the rod 15 under certain conditions, and this in turn prevents rocking movement of the rocker 10, with the result that the lever cannot be unlatched, or the mechanical interlocking released, as the case may be.

A circuit controller for governing the application of current to the distant switch or other function may be of any suitable construction, and for simplicity a circuit controller of the rotary drum type is illustrated. This circuit controller comprises a drum 16 of insulating material which is supported in suitable bearings and is provided with contact strips or segments, as 1718, fastened on its periphery. Contact springs, as 19-20. are supported and insulated in any suitable manner in position to cooperate with the strips 17-18 on the drum, thereby establishing certain circuit connections in the different positions of the drum. The drum 16 is arranged to be driven by a crank 21, which is connected by a link 22 to an adjustable block 23 on the tail-piece 24 of the lever. v

Referring to Figs. 2 to 7. the locking mechanism M comprises a suitable base or framework 13 having two uprights 25-25 supporting a rotary circuit controller drum 26. This drum 26 has anumber of contact strips 27 fastened thereto, and a number of contact fingers or springs 28, supported by a panel 29 of insulating material, cooperate with said strips. Also supported by the uprights 25 25 is an indication magnet comprising two cores 30 having pole pieces 31. On each core 30 is a coil 32 which is shorter than said core; and surrounding the cores 30 at the end opposite from the coils 32 are one or more yokes of copper or similar electrical conducting material. tlleeves 31 are used to hold the yokes 33 and the coils 32 in place. An angle lever 35 is pivotally mounted on a pin 36 in the upper end of the upright 25,, and the short end of this angle lever carries an armature 37 disposed opposite the pole pieces 31.

The locking mechanism comprises a sector 38 which is journaled between two standards 39 on a pin 10. This sector 38 is connected to the rod 15 which attached to the rocker 10, so that said sector moved back and forth as said rocker is shifted. The sector 38 is also connected by a link d1, having universal connections at its ends, to a crank arm connected to the shaft of the circuit controller drum 26. The upper edge of the sector 38 is cut away to leave normal and reverse locking shoulders 42*" and 42-; and pivotally supported on said sector are normal and reverse latches 13 and 13 which are pressed by springs '14 inward against a stop 15 to the position shown in Fig. 2. The outer ends of these latches d3 l-3 are concentric or flush with the outer edge of the sector 38; and when these latches are in their innermost position against the stop 15 they lap past the locking shoulders 42 4-2 as shown in Fig. 2. A U-shaped dog 16 is pivotally connected to the long arm of the lever 35 and rests upon the upper edge of the sector 38. The sides of this dog 46 are guided by vertical slots .in the upper ends of the standards 39. The upper face oi the cross connecting member of said dog 16 is beveled in opposite directions as shown in dotted lines in Fig. 2, and these beveled 'taces cooperate with a beveled piece attached to a curved strip 48 fastened to the outer edge of the sector 38, so as to force the dog downward between the two locking shoulders 4(2 42 A suitable cover 19 is provided for the locking mechanism.

Fig. 8 shows an electric lock embodying the invention applied to a well known type of dynamic indication interlocking system. Some parts of this system of interlocking, being well known and also disclosed in other patents and applications, have been shown conventionally, and their construction and operation will be only briefly referred to in so far as is necessary to obtain a clear understanding of the present invention. In the diagrammatic illustration oi Fig. 8, SM designates generally a circuit controller and motor of a suitable switch machine, such as is disclosed for example in the patent to V. K. Howe, 1,288,595, December 2st, 1918. IS designates the well known indication selector, and CP a cross protection relay operable upon alternating current but not direct current and adapted to interrupt the supply of current to the switch machine when crosses or other improper connections exist. The source of current is illustrated as a transformer T which is supplied with current from a suitable line circuit connected to the generator G. The circuit controller C and the electric. lock have been shown in a simplified manner.

Opcratz'0n.-Assume the parts to be in the normal position shown in F 8, and it is desired to move the switch to the reverse position. The operator presses the latch 4. and if the mechanical interlocking permits movement of the link 10, the die 6 is raised above the locking shoulder 8,. so that the lever L may be pulled to its other position. During this movement of the rocker 10, the sector 38 is moved from the position shown in Fig. 2, to that shown in Fig. 5 where the dog 16 engages the reverse shoulder 42 The sector 38 can not, therefore, be moved further in this counterclockwise direction until the dog 16 is raised, and consequently, the rocker 10 cannot move and prevents the final unlocking movement of the shaft 13. lVhen the lever L is moved, the drum 16 of the circuit controller C is moved from the position shown in F ig. 8 to the position where the contact strips 17-18 bridge the pairs of contact springs 1920, thereby establishing the reverse operating circuit, which may be traced as follows: commencing at one terminal of the transformer T, wire 50, contact 51 of the cross protection relay GP, wires 52. 53, indication selector magnet 5%, wire contacts 17-19, wire 56, reverse operating wire R, thence through the contacts and motor of the switch machine back along the common return connection 100 through the contact 57 of the cross protection relay UP and wire 58 back to the transformer T. This circuit supplies current to the switch machine which acts to move the switch points to the reverse position in the usual way. When the switch machine completes its cycle of operation, the motor (which is especially constructed so as to generate direct current dynamically) sends indication current out along the wire N, through wire 60, contacts 1820, wire 61, contacts 62, 63 and 641 of the indication selector (contact bar 63 havin been shifted by 'energization of mag net 54 wire 65, indication magnet 32, wire 66, cross protection relay GP, and wire 67 back along common wire 100 to the motor. This indication current, being direct current, attracts armature 37 and raises dog 46. As soon as the dog 46 is raised clear of the latch 43 this latch is swung by its spring 44 underneath said dog. (See Fig. 6). The operator now may complete the movement of the lever and the rocker 10, the dog at being now moved to the position shown in Fig. 7, thereby releasing the mechanical interlocking. The operation of moving the function from the reverse position back to the normal position is analogous to that described, and the circuits involved can be readily traced.

The latches 13 are provided so that the op erator is not compelled to complete the operation of the lever just atthe instant the indication is received. In other words, the indication current, although it flows only momentarily, gives a permanent release. This feature is of importance because it does not require the operator to give any attention to the lever while the function is operating and the indication is being received, and also because it obviates the inclination of the op erator to bind or jam the indication mechanism, as he might otherwise do if required to take advantage of the indication just at the instant it was received.

The indication magnet, while operating freely when supplied with direct current, will not act to attract its armature 37 when supplied with alternating current. The copper yoke 33 constitutes, in effect, a short-circuited turn around each core 30; and when alternating current flows through the coils 32, the alternating flux induces current in the yoke 83, which in accordance with well known laws, opposes the passage of flux through the cores and the armature 37 In this way, it is assured that no false indication will be received on account of alternating current from the operating source finding a path in some way through the indication magnet.

In the arrangement shown in Fig. 8, the circuit controller governing the operating and indication circuits, is operated by the tail-piece of the lever. I prefer this arrangement when the lever is used for controlling a switch; but when a signal is governed by the lever, the circuit controller drum 26 and associated parts coupled to the sector 38 may be employed, and the circuit controller C omitted. It will be evident that the circuit controller C, being operated by the tailpiece 24 of the lever, may have a much greater range of movement than in the case of the circuit controllerdrum 26 connected to the sector 38. This limited movement makes the use of the latter circuit controller undesirable in the case of a switch which requires both normal and reverse locking and normal and reverse indication circuits; whereas in the case of the signal which requires only reverse locking and a reverse indication circuit, the limited movement of the circuit controller drum 26 is sufficient.

I desire to have it understood that the construction and arrangement of parts and circuits illustrated is susceptible of change, and that my invention is not limited, to the exact construction and arrangement shown.

What I claim as new and desire to secure by Letters Patent of the United States, is

1. An electric lock for mechanical levers comprising a base and two uprights, a circuit controller drum pivotally supported between said uprights near their upper ends, a sector for operating said drum and having a locking shoulder, a lock dog cooperating with said sector, and means for actuating said lock dog comprising magnetic cores extending lengthwise of and below said control drum and supported by said uprights, an armature connected to said lock dog and disposed opposite one end of said cores, energizing windings on the other end portion of said cores, and a single conducting yoke on the ends of the cores adjacent the armature, said yoke being spaced from said windings, whereby said armature will be actuated to unlock said sector by direct current but not by alternating current supplied to said windings.

2. An electric lock for the levers of mechanical interlocking machines having preliminary locking comprising, a pivoted sector having a locking shoulder, a U-shaped dog straddling said sector and arranged to engage said shoulder, and a curved strip fastened at its one end to said sector and having inclined surf-aces adapted to engage said dog and force it into position to engage said shoulder, said strip being clear of said dog when said sector is in one extreme position, whereby said dog may be readily inspected and removed.

3. In an interlocking system, the combination with a lever of an interlocking machine, of an electric lock for said lever, said electric lock including an electro-magnetic operating means comprising cores of mag netic material, an energizing winding on one end portion of each core, a single conducting yoke on the cores at the other end, and nonmagnetic insulating means for spacing said windings and yoke to provide a leakage path for the flux produced by said windings and opposed by the magneto-motive-force due to current induced in said yoke when said windings are energized by alternating current.

In testimony whereof I have afiixed my signature.

EDWVIN C. LARRY.

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