US2706772A - Railway switch circuit controls - Google Patents

Description

April 9, 1955 J. c. MOCK 2,706,772

RAILWAY SWITCH CIRCUIT CONTROLS Filed March 30, 1950 2 sh t -s t 1 E INVENTOR.

JAMES C. MOCK BY: z

ATTORNEYS United States Patent controls for circuit conactuated by The present invention relates to circuit railroad switches and particularly to the trol mechanism located adjacent to and the movement of the switch point. l

in conventional installations of such control devices, the box containing the electrical making and breaking contacts is usually located on a tie end extension and actuated from the switch point by means of a rod extending under a rail to a swinging arm or crank carried by the box.

This location of the box is at a point of great vibration from passing rolling equipment and also requires the elimination of considerable ballast material to provide clearance for the crank and actuating rod.

Further, the crank arrangement necessarily produces bending stresses in the actuating rod with breaks often resulting.

Among the objects of the present invention is to provide a switch circuit control of such construction as to permit installation between the railroad rails where vibration is the least.

Another object is to provide a control installation in which all of the moving parts have a horizontal straight line motion.

Another object is a circuit control construction which will permit its being housed in a sufiiciently low vertical dimension as to allow its installation upon a tie between the rails. 7

Still another object is a switch control without springs, except the safety springs which are within the housing and thus protected.

Other advantages and objects will readily occur to those skilled in the art upon reference to the following description and accompanyingdrawings in which:-

Fig. 1 is a side elevation showing the complete control.

Fig. 2 is a side elevatlon of the control with parts in section.

Fig. 3 is a plan view of the circuit box with the cover partly removed.

Fig. 4 is a section on line 4--4 of Fig 3.

Fig. 5 is a section on line 55 of F g. 3.

Fig. 6 is an exploded perspective view of the cam block and carrier.

Fig. 7 is a view in elevation of an ad usting shim.

Fig. 8 is a partial view of a modification used when the control box is located outside of the rails.

In the drawings, the base line of Fig. 1 represents the upper surface of a railroad tie upon which are mounted the conventional bearing plates 10 and rails 11, while conventional switch points are shown at 12 and 12A.

Also mounted upon the tie, between rails 11, is a circuit control box 15 containing the circuit making and breaking contacts.

Although not shown in the drawings, the switch points 1212A will be hinged in the conventional manner and tied together by means of tie rods so that when the point 12 is against its adjacent ra l 11, the point 12A will be spaced from its adjacent rail a considerable distance, and vice versa.

From one of the switch points 12, an operating rod 16 extends to and into one compartment 15B of the control box 15 through a gland 16A and is attached to a cam block carrier 17, this being an inverted U- shaped element into which the cam block 18 is inserted from below.

2,706,772 Patented Apr. 19, 1955 This cam block 18, as shown in Fig. 6, comprises a two part block 18A and 18B which parts may be identical. Each of these parts consists of a body portion having adjacent one end cam surfaces 18C and 18D, these being inclined surfaces arranged on opposite sides of the body and inclined in the same direction. When the two parts 18A and 18B are assembled, all four cam surfaces are inclined in the same direction.

The cam block is preferably located in the carrier J by means of shims 19 of which there may be several of different thicknesses. By making the cam block 18 in two portions as indicated and assembling the two parts with a shim 19A between, accurate location of the cams 18C or 18D relative to each other may be had. Further, by shifting one or more of the shims 19 to the other end of the cam block, accurate location, within a limited range, of the block in the carrier may also be had.

As illustrated in Figs. 3 and 6, the cam block 18 is assembled into a unit by means of a bolt 18E extendlengthwise through the parts 18A and 18B and shim As seen best in Figs. 3 and 4, the cam block 18 is arranged to cooperate with a slide 20 having at one end a rectangular notch embracing the cam block and having cam surfaces 20A adapted to contact the cam surfaces 18C and 18D, to be moved thereby in a suitable guideway 20B.

The slide 20 extends laterally through the partition 15C into the contact containing portion 15A of the box 15 and carries an insulating block provided with abutments 40B arranged in pairs and provided with adjusting screws 20C for adjusting the gap between the members of a pair.

Arranged to lie between the members of each pair of abutments is a spring current carrying arm 21, anchored at 21A and connected through lead wire 213 to a suitable current source. Arranged on each side of arm 21 is a pair of spring arms 22 and 22A anchored respectively at 22B and 22C and having their free ends spaced a short distance but sufiiciently close to allow the arm 21 to contact one or the other when moved by the slide. The arm 22A is connected to its signal and or train control circuit through lead 22D while the arm 22 is connected to another signal or train control circuit.

As shown, the box 15 contains four sets of spring contact arms such as 21, 22, etc. and these will be connected to suitable current source and to signal and train control circuits in conventional manner, such circuits not being shown as they do not constitute part of the present invention.

In addition to the guideway 20B, the slide 20 may be further maintained in its rectilinear movement by means of the guide blocks 20D and a stirrup or hold down bar 20E extending through a suitable slot 20F in the slide.

It should be noted that in devices of this kind, the switch points 12, when operating properly, move a considerable distance from one position (open switch) to the other (closed switch), but it is necessary that signal change be accomplished during the initial movement. It is also necessary that the new circuit setting be not made until the switch points are substantially at the new position.

Accordingly, the cams 18C and 18D should be quite accurately located and should provide for moving the slide 20 quickly and at the ends of a considerable open circuit or neutral zone. In the present case, this is accomplished by the adjustability of the length of the cam block and by the use of the shims 19 to locate the block in the carrier.

Further, it is necessary that means be provided to indicate danger whenever the switch points move out of proper position due to breakage, wear or bad adjustment. Such indication in the present structure is provided for by the use of springs 25 located in the ends of the guide chamber 15B for the cam block carrier 17, and adapted to be put under compression during the final short movement of the carrier.

As just stated, the springs 25 are put under compression during the final short movement of the carrier. The distance traversed by the carrier in this compression movement is the same or slightly more than the horizontal distance between the ends of cam 18C or 18D. When, therefore, all adjustments are in order, the springs merely remain compressed. On the other hand, if such adjustments are not in order, the spring prevents the full movement of the block 17, or if inertia allows the movement to be completed, immediately pushes back the block far enough to break the circuit.

The modification indicated in Fig. 8 may be used when, for some reason, it is desired to locate the control box 15 on a tie end or other support outside of the rails; in this form, the rod 116 will be provided with an offset joint or connection 116A and the portion 116B connected to the switch point 112, thus lowered to pass under the rail 111.

In either, however, the operation of the control circuits is through a straight line movement of the moving parts so that no bending stresses are applied to the operating rod and all of the weather-vulnerable parts are enclosed.

I claim:

1. In railway switch circuit controls, circuit making and breaking means, a horizontally arranged cam member for actuating said means, said cam member being provided with an elongated body portion having a rectangular cross section, and being provided on its opposite vertical faces and adjacent both ends with short angularly arranged cam surface portions arranged parallel to each other, the two angular portions at each end being directly opposite each other and a cam follower member connected to the making and breaking means and coacting with both of said directly opposite angular portions.

2. In railway switch circuit controls, circuit making and breaking means, a cam member for actuating said means, said cam member being provided with an elongated body portion divided intermediate its ends and having a rectangular cross section, and being provided on two of its opposite faces and adjacent both ends with short angularly arranged cam surface portions arranged parallel to each other, the two angular portions at each end being directly opposite each other, and means for fixing the portions of said body together said fixing means including means whereby the distance from the cams at one end to those at the other may be accurately adjusted.

References Cited in the file of this patent UNITED STATES PATENTS 920,030 Cunningham Apr. 27, 1909 1,011,801 Johnson Dec. 12, 1911 1,025,585 Nelson May 7, 1912 1,233,531 Wiegand July 17, 1917 1,762,789 Nordholm June 10, 1930

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