US3427990A

US3427990A - Railroad ballast handling system

Info

Publication number: US3427990A
Application number: US672406A
Authority: US
Inventors: John F Bryan Jr
Original assignee: TRAKWORK EQUIPMENT CO
Current assignee: TRAKWORK EQUIPMENT CO
Priority date: 1964-09-03
Filing date: 1967-07-11
Publication date: 1969-02-18
Anticipated expiration: 1986-02-18

Description

Feb. 18, 1969 J. F. BRYAN, JR

RAILROAD BALLAST HANDLING SYSTEM Sheet Original Filed Sept. 5, 1964 INVENTOR. JOHN F BRYAN, JR.

J. F. BRYAN, JR

RAILROAD BALLAST HANDLING SYSTEM Feb. 18, 1969 2 off) Sheet Original Filed Sept. 3, 1964 INVENTOR. JOHN F. BRYAN, JR.

Feh 18, 1969 J. F. BRYAN, JR

RAILROAD BALLAST HANDLING SYSTEM Sheet Original Filed Sept. 5, 1964 INVENTOR. RYAN, JR.

Feb. 18, 1969 J. F. BRYAN, JR

RAILROAD BALLAST HANDLING SYSTEM Sheet 4 of 5 Original Filed Sept.

z Q on yo 0 o a INVENTOR. JOHN F. BRYAN, JR.

Feb. 18, 1969 J. r-. BRYAN, JR

RAILROAD BALLAST HANDLING SYSTEM Sheet FIG. 8

I INVENTOR JOHN F. BRYAN, JR.

United States Patent 3,427 990 RAILROAD BALLAST HANDLING SYSTEM John F. Bryan, Jr., Dallas, Tex., assignor to Trakwork gquipment Company, Irving, Tex., a corporation of exas Original application Sept. 3, 1964, Ser. No. 387,114, now Patent No. 3,339,493. Divided and this application July 11, 1967, Ser. No. 672,406 US. Cl. 104-2 3 Claims Int. Cl. E01b 27/06; E02f 5/00 ABSTRACT OF THE DISCLOSURE This invention relates to the method of automatically removing ballast from between railroad ties by means of an articulated cutting head adjustable behind a track vehicle to drive a cutting chain at a predetermined depth below the top of a rail. The method includes progressively raising the rails and the ties above the normal base and inserting ballast under the ends of the ties to support them temporarily at a level above the base and continuously removing all ballast above said base in a zone which trails the first Zone.

This is a division of application Ser. No. 387,114, filed Sept. 3, 1964, now Patent No. 3,339,493.

This invention relates to a system for removal and handling of ballast under railroad track and more particularly to use of an articulated cutting head driving a cutting chain which is adjustable in position behind a track vehicle to pass beneath the track at a predetermined depth below the top of the rail in a trailing zone while plowing the ties upward in a first zone and supporting the same by ballast temporarily placed thereunder to permit the chain to work beneath the ties down to the normal base of the track.

Service operations on a railroad track include the removal of ballast from beneath the railroad cross ties or from the zones between the ties for removal of debris which fouls the ballast and accelerates deterioration of the ties.

A number of systems have been used in the prior art which involves use of a chain driven beneath the railroad ties for removal of the ballast. The present invention relates to an improved system in which a cutting head may be towed behind a vehicle to engage and remove ballast from beneath the railroad ties while permitting ready adjustment both in the elevation of the cutting chain, the lateral position thereof, and ultimately in the configuration ofthe cutting head. The cutting head may be adjusted from a Work configuration in which the chain passes over supporting rollers or Wheels adjacent to the ends of the ties and courses beneath the ties to a folded configuration in which the cutting head lies within the perimeter of a prescribed clearance outline. In a further aspect, the invention relates to a suspended cutter head towed behind a railroad car by relatively long towbars at least one of which is employed for transmission of power to the cutting head. A pair of hydraulic elevators are employed for controlling the elevation of the cutter head relative to the railroad car. At least one hydraulic control means is employed for laterally positioning the cutter head relative to the railroad car. The system provides for automatic handling of ballast removed from beneath the ties by depositing the same, through the use of the cutting chain during an upward course thereof, onto a belt conveyer system.

The invention further relates to a method of skeletonizing a railroad track. In skeletonizing the track is progressively elevated and is supported at a slightly elevated position by tamping ballast under the ends of ties at predetermined spaced tie locations. Ballast then is continuously plowed inwardly under the ends of each of the ties to provide continuous tie support for the mechanism supporting the plows and the ballast treating unit. Thereafter, the ballast is continuously cut and removed from the ballast section for a depth below the bottom of the elevated ties corresponding with the original base of the ties. The ties are automatically lowered back to the surface of the plowed bed at a location trailing the point of contact with the ballast face.

More particularly, in accordance with the present invention, a system is used for removal of ballast from be neath railroad ties. A wheeled frame is powered for travel along a railroad track which tows a cutting head having a cutting chain. The chain is driven along a path having a lower course which is generally horizontal and located beneath the ties. Towbars extend generally parallel between the frame and coupling points on the cutting head to tow the cutting head behind the frame, crowding the chain into the ballast. A drive means is provided for driving the chain in the cutting head. A first support means is connected between the frame and the cutting head for bodily raising and lowering the cutting head to control the elevation of the lower course of the chain. Support means also extend between the cutting head and the frame for adjusting the lateral position of the cutting head.

In a further aspect, there is provided a method of skeletonizing a railroad track which has been raised from its normal elevation with ballast tamped beneath ties located at predetermined spaced-apart tie locations as temporary support of the track. The method includes plowing successive loose ties upward into engagement with the elevated rail while continuously plowing ballast inwardly under the ends of each of the ties in a support-forming zone to provide temporary support for all of the ties. In a working zone which continuously trails the supportforming zone, ballast is continuously cut and removed from beneath and from between the ties to a depth corresponding with the normal elevation of the bottom of the ties.

For a more complete understanding of the present invention and for further objects and advantages thereof, reference may now be had to the following description taken in conjunction with the accompanying drawings in which:

FIGURE 1 is a side view of a embodiment of the present invention;

FIGURE 2 is a top view of the unit of FIGURE 1;

FIGURE 3 is a rear view of the unit of FIGURE 1;

FIGURE 4 is an enlarged rear view of the cutting head of FIGURE 1;

FIGURE 5 illustrates a link for the chain of FIGURES 1-4;

FIGURE 6 illustrates the link of FIGURE 5 viewed from the left end;

FIGURE 7 illustrates a ballast treating train;

FIGURE .8 illustrates one form of control in the present invention: and

FIGURE 9 illustrates a modified form of control system.

FIGURES 1-3 illustrate a system for undercutting and removing ballast from beneath the ties of the railroad track 10. The track 10 is mounted in the usual manner on the ties which are supported by ballast. Ballast fouled with fine debris, if permitted to remain untreated would accelerate deterioration of the ties and early replacement of the ties on a large scale may be required. It has been found that if the ballast is removed and treated and replaced, the the life of the track is extended. In accordance with the present invention, there is provided a ballast removing and treating mechanism which is versatile in its ability to meet varying conditions encountered along railroad trackage.

A vehicle 11, FIGURE 1, includes a main frame '12 supported on two

tandem axle assemblies

13 and 14. The

assemblies

13 and 14 are conventional units such as ordinarily employed in heavy duty trucks and the like, modified, however, to receive flanged wheels for track use. Both axle assemblies are driven from a motor 15, the drive coupling not being shown in FIGURE 1.

Frame 12 also supports a torque converter 16 which is coupled by a two-stage chain drive 18 from the output shaft 16' to a drive shaft 17. The chain drive 18 provides for speed reduction related to the nature of the work encountered in the ballast as will hereinafter be described.

Trailing the vehicle 11 is a cutting head 20. The cutting head 20 includes a pair of

side members

21 and 22. The

side members

21 and 22 are interconnected by cross members as will hereinafter be described such that it forms a rigid framework. Attached to the cutting head 20 are three

towbars

23, 24, and 25, only bars 23 and 25 being seen in FIGURE 1. The bar 23 is pivotally coupled through pin to a bracket on the bottom of the frame 12. At the trailing end bar 23 is coupled through through pin 31 to a bracket on the lower frame portion member 21.

As best seen in FIGURE 2, the second towbar 24 is pivotally coupled to the frame 12 through pin 32. The trailing end of the bar 24 is connected through pin 33 to a bracket on the lower portion of the cutter head frame.

The third towbar 25 serves a dual function of linking the cutter head 20 to the vehicle 11 at a third point and to transmit rotary power to the cutter head 20. More particularly, the bar 25 is coupled through a universal joint 35 to the output shaft 17 in the transmission system. At the trailing end, bar 25 is coupled through a universal joint 36 to a drive shaft 37 on the cutter head 20.

From the foregoing, it will be seen that the cutter head 20 is to be towed behind the vehicle 11 by means of the three towbars 23-25. Hydraulic clinder means are then used to control the elevation of the cutter head 20 and the lateral position thereof, relative to frame 12, as will now be described.

Three couplings are provided between the frame 12 and the cutter head 20 by

hydraulic cylinders

40, 41, and 42. The cylinders 40 and 41 coupled between the frame 12 and the cutter head 20 serve to control elevation. As best shown in FIGURE 1, the cylinder 40 is pivotally connected at the lower end through pin 45 to a bracket on frame 12. At the upper end, the piston in cylinder 40 is pivotally connected through pin 46 to a bracket located near the upper edge of the cutter head 20. Cylinder 40 extends upwardly and rearwardly from frame 12. In actual practice, the orientation of cylinder 40, for example, may be substantially vertical and will serve along with the cylinder 41 to control the elevation of the head 20 relative to the track 10.

The third cylinder 42 is connected between the frame 12 and the cutting head 20 to control the lateral position of the cutting head relative to the track 10. Thus, the cutting head may be moved vertically or horizontally. Since the towbars are relatively long, the head 20 follows a relatively large diameter are as the elevation thereof is changed. At the same time power is transmitted by way of shaft 25 to the cutting head 20.

It will be helpful now to refer to FIGURES 3 and 4 which illustrate the cutting head as viewed from the rear. The frame plate 22 has a downwardly extending rectangular section 50 which serves as a ballast box and which serves also to house and provide support for a shaft 51 on which an idler wheel 52 (shown dotted) is supported. A cutting chain 53 passes over idler wheel 52. The frame plate 22 and its mating frame plate 21 are of essentially the same configuration etxending upwardly to form an extension '54 of the ballast box 50. The frame plate 22 is coupled to frame palte 21 on the upper outer perimeter by two cylindrical struts 55 and 56. The lower edges 57 of the

frame plates

21 and 22 are generally horizontal extending above and spanning the rails 10. The

frame plates

21 and 22 also have a central aperture 58 therein. A conveyer belt 60 shown in FIGURE 1 passes over a drum 61 mounted at the bottom of the triangular-shaped opening 58 in the

plates

21 and 22.

The

plates

21 and 22 are further coupled together by a plate 65 forming a bottom closure for the ballast box 50. The plate 65 has a lower leg 66 which is slotted to accommodate passage therethrough of the idler 52. The ballast box plate 65 has a downwardly extending leg 67 and a section 68 which extends parallel to the lower sloping surface. Section 69 extends upward along the perimeter of the opening 58. The plate 65 terminates at the point 70 so that ballast propelled into the ballast box 60 will be drawn upwardly by the chain 53 to point 70 and will spill onto the conveyer belt passing over drum 61 for removal to a vehicle on track 10 positioned rearwardly of the vehicle 11.

The

plates

21 and 22 are further interconnected by a baflle plate 75 which is secured along the upper righthand margin of the opening 58. The battle plate 75 serves as a backstop for ballast tossed towards the conveyer belt by the chain 53.

The cutter chain '53 passes over a second idler pulley which is mounted on a shaft 8-1 at the lower end of an arm 82. The arm 82 is pivoted between the

frames

21 and 22 as at pin 83. The arm 82 is coupled to the cutter head frame at a second point by a hydraulic cylinder 85 which is connected to the frame at pin 86. The piston rod 87 for cylinder 85 is coupled at pin 88 to the arm 82. The hydraulic cylinder 85 is not seen in FIGURES l and 2 because it is mounted on the bottom of the cutter head frame approximately centrally of the cutting chain 53. The cylinder 85 serves to position the idler sprocket 80 beyond the end of the ties and to control the width of ballast to be removed by the chain 53.

A drive sprocket 90 over which the chain 53 is threaded drives the chain clockwise as viewed in FIGURE 4. The sprocket is mounted on shaft 37 which in turn is journaled in a drive frame 91 formed by a pair of arms one of which may be seen in FIGURE 4. More particularly, the arms of the drive frame 91 are pivoted as at pin 92 in an car at an intermediate point along the arm 82. The drive frame 91 is of irregular shape to permit the cutter head to be folded for transit as will hereinafter be described. The arms of the drive frame are coupled by a strut 93 located near the pivot pin 92. The arms are also coupled together by a strut 94. The shaft 37 extends between the two arms at a point above the strut 94. A third strut 95 for the drive frame 91 is positioned at the upper extremity thereof. The upper end of the drive frame 91 is coupled to the

main frame members

21 and 22 by

hydraulic cylinders

96 and 97. Only the cylinder 96 is shown in FIGURES 3 and 4. The lower end of the cylinder 96 is connected through a pin 98 to the frame plate 22. As best seen in FIGURE 1, the pin 98 passes through a stirrup which is formed by the plate 22 and a second 99 is secured to the pipe 56. The upper end of the piston rod 100 is connected to the drive frame 91 through pin 10'1. In a similar manner, the second cylinder 97 is connected between stirrups on

struts

56 and 95. Thus,

cylinders

85, 96, and 97 are employed to control the width of the cut made by the chain 53 on the bottom course and the tension on the chain for any given width.

The foregoing linkages present in the cutting head for support of the chain will permit the cutting head to be folded to a position within the limits of a standard railroad diagram for transit from one location to another. More particularly, in FIGURE 3, an outline has been superimposed upon the cutting head and the supporting mechanism to represent the standard clearance outline. When it is desired to transport the cutting head from one location to another, one joint in the chain is removed to permit the chain to be withdrawn from its lower course. The cylinders 40 and 41 are then actuated to elevate the cutting head. Cylinder 42 is then adjusted to center the cutting head within the clearance outline 105. The cylinder 85 is actuated to retract the arm 82 to a position within the clearance outline. The configuration of the arm 82 and the drive frame 91 are such that they permit the cutting head to be folded to within the clearance outline 105.

FIGURES 5 and 6 illustrate one form of a cutting link which serves to make up the chain 53. Link 110 is provided with a body 1111 which rides on the sprockets 80, and 90 and rides over the surface of the idler wheel 52.

A side bar 112, FIGURE 5, on the front of the link, is I provided with a boss 113 which serves as a bearing for a coupling pin. At the back of each link and in alignment with the boss 113 is a clevis. A pin 114 passes through the clevis and is keyed into the clevis by a cotter pin 115. A second arm 116 is provided with a boss 11 17 which also serves as a hearing. A clevis is positioned on the back of the body 111 for mating a boss on an adjacent link. A pin 118 pascs through the clevis and is keyed into the clevis by a cotter 119.

The cutting tip 120 of link 110' is in the form of a relatively wide blade. The blade extends at an angle forwardly from the body 111 and serves as a cutting tool and as a rake to propel the ballast cut from the understructured body of ballast away from the working face. In this connection, it will be noted that the side bar 112 is of substantially reduced section to minimize obstruction to passage of the ballast toward the center of link 110. As best seen in FIGURE 6, side bar 112 has a thickness x. In contrast, the bar 116 is of a greater width y to oppose flow of the ballast beyond the same and to control the ballast such that it will occupy the zone 125 between the

arms

112 and 116 and will be moved by the body section 111 from the place of dislodgetment into the ballast box and then upward onto the conveyer. 1

FIGURE 6 is a view of the link from the left end as shown in FIGURE 5. As seen in FIGURE 6, the head of the pin 119 is an oblong head which seats against the end of lug 122. In a similar manner, the head of the pin 114 is seated between

ribs

123 and 124. The later ribs serve to strengthen the cutting blade and at the same time prevent rotation of the pin in its clevis.

In placing the system in operation, the unit 11 is located at a beginning site and the ballast or one tie is re" moved from beneath the track in order to thread the chain therebeneath. The ends of the chain are then coupled together so that the chain encompasses the track and the ties. Tension is placed on the chain by actuation of the

cylinders

85, 96, and 97. Upon application of power to the drive sprocket 90, the cutter head 20 may be lowered to the desired depth. The vehicle 11 may then be moved forward by application of power to the tandem axle units to crowd the tips of the cutter chain 53 against the workinlg face. i The chain is driven in a clockwise direction by the top sprocket 90 at a nominal rate of 600 feet per minute. The ballast is cut or broken loose and dragged into the confined ballast box 50. The stop plate 65 prevents the material from falling back into the track area. When the chain has turned the corner in the ballast box, it becomes essentially a bucket elevator, raising the material from the box and depositing it on the conveyer which extends back from the machine. The ballast can thus be cleaned and restored to the track or wasted as desired.

The two trailing

links

23 and 24 are attached to the lower portion of the cutting head 20 on either side. These links carry the major portion of the force required to crowd the digging chain into the ballast. The drive shaft 25 which powers the top sprocket is of fixed length and also serves as a locating member for the cutting head.

The cutting head is positioned in the plane determined by the three links 23-25 by means of the two vertical hydraulic cylinders 40 and 41 and the lateral hydraulic cylinder 42. Actuating these cylinders separately permits an operator to position the cutting head for various depths of cut, to the right or left, or should it be desired, lower on one side than the other. When both the right hand and left hand vertical hydraulic cylinders are extended, the loading frame is raised and shifted .laterally. The left hand sprocket positioning arm is then retracted which permits the assembly to come within the standard railway clearance diagram.

Scarifying teeth are provided at the forward end of the machine 11 with inclined blades so arranged as to wedge shoulder ballast underneath the ends of the cross ties. This feature is utilized in cases where it is desirable to remove only the ballast between the ties without lowering the elevation of the track. This operation is known as skeletonizing or stripping. In order to accomplish this, a tamping jack precedes the vehicle 11. It is used to raise the track a distance equal to the thickness of the chain cut. The track is raised and ballast tamped under the cross tie ends at intervals of five or six ties. These intervals are too far apart and the compaction provided by the tampin'g jack generally is insufficient to bear the weight of the ballast removing machine 11. The scarifier is used to wedge sufficient ballast under the ends of each cross tie to support the track under the weight of the machine with minimum settling.

More particularly, an inner scarifying tooth on each side of the machine is arranged so that its leading end will pass under the ties which are left down when the track is raised. The inner teeth wedge the ties up against the rail, where they are held by the ballast. This permits unspiking defective ties and removing tie plates in ad- Vance of the undenouting operation, thereby facilitating replacement of the ties after undercutting.

In FIGURES 1 and 2 it will be noted that scarifiers are mounted at the front of the frame 12. More particularly, wings 1150 and 151 are pivotally mounted through pins #152 and 153 on opposite sides of the frame 12. As shown in FIGURE 1, the wing 152 extends downward from the frame 12. As shown in FIGURE 2, it extends outwardly from frame 12. The wing supports three

scarifier teeth

155, 156, and 157. Teeth 155 and L156 are mounted on

shanks

158 and 159. The depth of the cutting teeth can be adjusted by controlling the angle of the wing I150 and by adjusting the point at which the shank is secured to the wing. As indicated each of shanks carrying the scarifying teeth have holes passing therethrough to accommodate pins such as the pin 160 to secure the shank to the wing.

As best seen in FIGURE 2, the scarifying tooth 157 has an inwardly sloping face. As shown in FIGURE 1, it has an upwardly sloping surface. FIGURE 3 shows the shank 161 on which the tooth [1'57 is mounted extending downwardly and inwardly under the ends of the ties. The inner face of the tooth 157 is vertical. The bottom surface of the tooth 157 is flat. Since the surface 162 is canted inwardly, the tooth 157 serves to plow ballast inwardly under the ties and to force the same up against the ties to provide temporary support for skeletonizing operations. It may also engage ties which are unspiked prior to passage of the scarifier to elevate them and prop them up under the rail for temporary support of the vehicle 11.

A frame is provided for control of

wings

150 and 151. It includes a pair of posts 1171 and 172 which are supported on opposite sides of the frame and are coupled across the top by a member which spans the motor 15. A hydraulic cylinder .173 is connected through a pin 174 to a clevis at the top of the post 171. The piston of cylinder 173 is connected through pin 175 to a clevis on the wing :150. The cylinder 173 thus provides control of the position of the wing 150. In a similar manner, a hydraulic cylinder 175 controls the position of wing 151.

The scarifier may loosen the ballast on the shoulder of the track bed well in advance of the cutting head 20. The ballast along the track edge is loosened so that the frame portions of the cutting head will be able to be moved through the loosened debris outside the limits of the course of the cutting chain without difliculty. More particularly, as shown in FIGURES 1 and 2, the ballast box 50 has a back plate which is a downward extension of the frame plate 22. The back plate extends down to the level of the lower margin 180. A side plate 181 on the box 50 is coupled to the rear section by a hinge 182. A reinforcing body 183 is applied to the outside of the end plate 181.

As shown in FIGURE 2, the end plate 181 of the ballast box is coupled by a link 185 to the frame plate 21. The link 185 is adjustable so that the end plate 181 may be oriented parallel to the frame plate 12 or may be angled outward to plow ballast into the ballast box as the cutting head moves forward. Although not shown, the front frame plate 21 does not extend down to the bottom level 180, but is terminated above the normal level of the ballast surface. By this means the ballast untouched by the chain but loosened by the scarifier can flow freely into the ballast box as the cutting head moves forward. The rear surface of the ballast box extends down to the level 180 as shown in FIGURE 3 and thus serves to scrape or finish the exposed ballast surface adjacent to the left margin of the chain 50.

Motor serves to power the entire unit. As shown in FIGURE 2, the output shaft 190 is coupled to the torque converter 16. A second output shaft is coupled to a pump 191 which is connected through suitable controls in the cab 192 to each of the hydraulic cylinders in the system. The tank 193 serves as a reservoir for hydraulic oil and tank 194 is a fuel tank. While hydraulic lines have not been shown, the mode of control of hydraulic cylinders is well known and for this reason the details have been omitted. Three controls are provided in the cab 192 for individual control of the three positioning

hydraulic cylinders

40, 41, and 42. A fourth control serves to actuate the two

cylinders

96 and 97 to control the position of the drive sprocket 90. A fifth control is provided for the hydraulic cylinder 85 which controls the position of the arm 82 carrying the idler sprocket 80. Sixth and seventh controls are provided for independent actuation of the

cylinders

173 and 175 on the scarifier wings. The controls are represented by the bank of levers 196 and cab 192.

A third output shaft 197 from the motor 15 is coupled through a drive shaft (not shown) to power the

tandem axles

13 and 14. Such transmission systems are well known and for this reason have not been detailed in the drawings. The engine 15 in the form of a GMC twin 671, 300 horsepower engine is suitable. The torque converter 16, in the form of ten-inch, three stage torque converter with reversible gears manufactured and sold by Twin Disc Clutch Company, Rockford, 111., as model CRR- 10043 is satisfactory. Such a torque converter has an output between 400 and 700 r.p.m. This is reduced through linkage 18 by a factor of about 7 so that the drive sprocket 90 rotates up to about 100 r.p.m.

In FIGURE 7 the vehicle 11 is illustrated in operative relation with a ballast handling or surge car 200. A conveyer belt unit 201 is located between the cutting head 20 and the car 200 to apply a towing force to the car 200. A hydraulic motor 202 is shown diagrammatically in driving relation with respect to the conveyer belt until 201. The motor 202 is hydraulically powered from the engine 15 by a suitable pressure line (not shown). The car 200 may be loaded with waste ballast for delivery at some remote point or it may be provided with a cleaner and/or conveyer to spoil the ballast and/or unwanted debris along the side of the track right-of-way.

A control system for the vehicle 11 and the cutting head 20 is illustrated diagrammatically in FIGURE 8. The motor 15 drives pump 191 to pump hydraulic fluid from the tank 193 through a line 210, a check valve 211, to a hydraulic motor 212. A return line 213 connected to motor 212 delivers hydraulic fluid back to tank 193. The motor 212 is coupled by way of the linkage 214 to the drive wheels of vehicle 11 as represented by the wheel 215.

A ventilating line 220 is connected to line 210 and is provided to bypass hydraulic fluid from line 210, by way of valve 221 and line 222, to tank 193. The speed of the vehicle is reduced to the extent that valve 221 is opened. The valve 221 is controlled by a centrifugal switch 223 which is driven from the output of a torque converter 16 which drives sprocket and the chain 53. In operation, the pump 191 is set to produce a selected pressure for operation of the motor 212. The torque converter 16 is set to drive chain 53 at a predetemined speed, preferably of the order of about 600 feet per minute. The torque converter 16 has an output speed dependent upon the load on the chain 53. Switch 223 operates to energize valve 221 to bypass hydraulic fluid to motor 212 at a speed at which the torque converter 16 is about to become stalled. This stops forward movement of the vehicle 11 and permits the chain 53 to clear itself, whereupon the torque converter 16 brings the chain 53 up to its speed again, valve 221 closes, and the normal forward progress of the vehicle 11 is resumed.

In the embodiment illustrated in FIGURE 8, the pump 191 may be a variable volume pressure compensated pump of the type manufactured and sold by Vickers Inc. Division, Sperry Rand Corp., Detroit, Mich., and identified as Model PUB. 29L510c-1 0.

The motor 212 may be a propelling drive motor of the type manufactured and sold by Oliver Tyrone Corp., Pittsburgh, Pa., and identified as Model GMA3-300.

The solenoid operated valve unit 221 may be of the type manufactured and sold by Vickers Inc. Division, Sperry Rand Corp., Detroit, Mich., and identified as CT. 5-06FG-10.

The centrifugal switch unit 223 may be of the type manufactured and sold by Allen Bradley, Milwaukee, Wis., and identified as a zero speed plugging switch Cat. #808F1, Series C.

In FIGURE 8, the control function for varying the forward speed of the vehicle is produced by the centrifugal switch 223. In the modification of the system as shown in FIGURE 9, the control function is sensed hydraulically. While the system of FIGURE 8 is preferred, it will be understood that a system such as shown in FIG- URE 9 may be found to be suitable. Where consistent, like parts have been given the same reference characters as in FIGURES 18.

In FIGURE 9 the drive for motor 215 through line 210 is vented or bypassed to tank 193 by way of a variable flow, pressure compensated control unit 230. Line 210 is connected to the input to the control unit 230. The output line 231 leads to the tank 193. A second pump 232, a vane type pressure pump, is supplied from tank 193 and drives one end of double rod ended cylinder control unit 234. The pump applies pressure above a piston 235 in unit 234 opposing the force of a spring 236. The piston rod 237 is coupled by linkage 238 to the variable control on the valve unit 230. A line 239 is connected from pump 232 by way of a fixed orifice 240 leading to a reference input to the unit 230. The pump 232 is driven, as by linkage 241, from the output of the torque converter 16. When the torque converter 16 approaches a stalling speed, the output pressure in unit 234 from pump 232 is reduced so that spring 236 actuates the control unit 230 to bypass hydraulic fluid normally flowing through motor 212 and shunts the same to tank 193.

In FIGURE 9, the pump 209 may be a fixed displace- 9 ment pump of the type manufactured and sold by Oliver Tyrone Corp., Pittsburgh, Pa., and identified as 20,150 A Gear Pump.

The sensing pump 232 may be a vane pump of the type manufactured and sold by Gresen Mfg. Co., Minneapolis 18, Minn., Catalog No. TC-12S7550B-CW. The double rod ended cylinder 234 may be of the type manufactured and sold by Oftman-Miller Machine Co., Inc., Hammond, Ind., Model No. CDER HYD-J. 3x6.

The pressure compensated variable flow control unit 230 may be of the type manufactured and sold by Waterman Hydraulics Corporation, Evanston, Ill., Catalog No. 1441-R-4.5-28 Pressure Pump.

The fixed orifice 240 may be of the type manufactured and sold by Manatrol, Elyria, N.Y., and identified as Control Valve Model No. N-1200B.

A relief valve 242 was connected to the line 210 to protect against over pressure and may be of the type manufactured and sold by Dennison Engineering Division of American Brake Shoe Co., Columbus, Ohio, and identified as relief valve RV-20.

The foregoing description has dealt with the preferred embodiment of the invention in which a vehicle, a car or wheeled frame, is designed to travel along a railroad track and which carries a prime mover or motor 15 which provides drive power for the vehicle as well as for the ballast cutting chain. The prime mover is coupled to the chain by a mechanical drive including the torque converter 16 which has an output speed dependent upon the load on the chain. The speed of the chain is sensed and drive power to the vehicle is lowered, modulated, or even completely removed when the speed of the chain is lowered. Preferably, the forward progress of the vehicle is arrested as the speed of the chain approaches stalling speed of the torque converter 16. The cutting head in which the chain is propelled is supported from the vehicle by adjustable means which permit location of the chain in its working position and which permit folding of the cutting head for transit over the track. Thus, the cuttinlg head is bodily raised and lowered, depending upon the requirements at a given location.

In a preferred form, the cutting chain for working the ballast from under the railroad track involves the elongated body member 111 having a blade 120 thereon which extends angularly from the right-hand end of the body as viewed in FIGURE 5. Male and female clevis portions are integral with the body 111 adjacent to the root of the blade 120 and have pin-receiving ports centered on a plane passing through the body, with respect to which the blade 120 is symmetrical. The male portion 112 has a lateral dimension parallel to the above plane which substantially exceeds the lateral dimension thereof normal to the plane. The other male and female clevis portions of each chain link are integral with the body 11 at points remote from the blade 120 and have pin-receiving ports axially aligned with the ports in the clevis portions adjacent to the blade 120.

Links of the above character, coupled together, may form a continuous chain which delivers ballast from beneath the railroad track into the compartment or ballast box 50 housing the idler wheel 52. The idler wheel 52 includes a hub portion 52a, and a chain guide disk 52b over which the chain passes. The body portion 111 of each chain link bears on disk 52b. Rearward of disk 52b and mounted on shaft 51 is a. large pusher disk 52c which provides a surface against which the left-hand end of the link, as viewed in FIGURE 5, may hear. The portion 66 of plate 65 is slotted and fits over the guide disk 52b and the pusher disk 52c. Ballast delivered into the ballast box 50 is then propelled upward along the sloping surface of ballast deposited in the compartment formed by the plate 65 and then is delivered onto the conveyor belt or track 61.

Having described the invention in connection with certain specific embodiments thereof, it is to be understood that further modifications may now suggest themselves to those skilled in the art and it is intended to cover such modifications as fall within the scope of the appended claims.

What is claimed is:

1. In skeletonizing a railroad track in which the track has been raised from its normal elevation and ballast inserted at predetermined spaced-apart tie locations under a fraction of the ties temporarily to support the ele- 0 vated track, the method which comprises:

(a) successively plowing loose ties upward into engagement with the elevated rail,

(b) continuously plowing ballast inwardly in a supportforming zone under ends of each of the ties to provide support for every tie, and

(c) in a working zone which trails said support-forming zone, continuously cutting and removing ballast from beneath and between the ties to a depth corresponding with the normal elevation of the bottom of said ties.

2. The method of skeletonizing a railroad track which comprises:

(a) progressively raising the track above its normal base and inserting ballast at predetermined spacedapart tie locations for support of a fraction of the ties temporarily to support the track above said base,

(lb) continuously plowing ballast inwardly and upwardly in a support-forming zone extending under the ends of each of the ties to provide support for every tie, and

(c) in a working zone which trails said support-forming zone, continuously cutting and removing ballast from beneath the track to a depth generally corresponding with the elevation of said base.

3. The method of skeletonizing a railroad track which comprises:

(a) continuously plowing the ends of the ties upwardly to an elevation above the normal elevation while plowing ballast inwardly in a support-forming zone under ends of each of the ties to provide support for every tie, and

(b) in a working zone which trails said support-forming zone continuously cutting and removing ballast from beneath and between the ties to a depth corresponding with the normal elevation of the bottom of said ties.

References Cited UNITED STATES PATENTS ARTHUR L. LA POINT, Primary Examiner. R. A. BERTSCH, Assistant Examiner.

US. Cl. X.R.