Mobile Track Working Machine

Abstract

The advancement of a mobile track working machine from operating station to operating station is accurately controlled by the combined use of a control element actuatable by a selected track part, such as a tie spike or bolt, a signal pulse generator operatively associated with the control element and producing signal pulses indicating the distance of the advancement, and a signal pulse recording instrument connected to the generator and receiving the signal pulses therefrom upon actuation of the control element by the selected track part.

Description

The present invention relates to improvements in mobile machines carrying tool means for working at spaced consecutive operating stations along a track comprised of rails fastened to ties. The advancement of such machines from station to station is controlled by a control element actuatable by a selected track part, and the lowering of the tool means into an operating position may also be so controlled.

In known mobile track working machines of this type, it has been proposed to make the position between the control element, which usually has the form of a pivotal tie sensing lever, variable so as to make the advancement of the machine adaptable to different track conditions, such as upgrades or inclines. Such arrangements have not proved to be satisfactory under all conditions, particularly since the adjustment of the control element has been relatively complicated. Also, except for visually observing the track, the operator cannot control the accurate positioning of the machine in respect of the point where the tools are working.

It has also been proposed to control the advancement of the machine in response to an adjustable time relay or to the distance traveled by the machine from the last point of work. Such systems have the major disadvantage that any occurring errors are necessarily added as the machine advances from station to station so that, after a relatively short period of time, the time or distance adjustment is completely inaccurate. In addition, in these systems, too, only visual observation is available to the operator for determining whether the machine is in the correct position for work.

It is the primary object of this invention to overcome these disadvantages and to assure proper centering of the working tools at each station, regardless of any irregularities in the crib widths in the particular track section in which the machine works.

This and other objects are accomplished in accordance with the invention by providing a signal pulse generator operatively associated with the control element, which generator produces signal pulses indicating the distance of advancement of the machine and a signal pulse recording or indicating instrument connected to the generator and receiving the signal pulses therefrom upon actuation of the control element by a selected track part.

By combining the control element, the pulse generator and the recording instrument, whose recorded or indicated signal pulses are used to control the advancement of the machine, the control element is responsive to the signal pulse generator and the machine advancement is responsive to the recording instrument signals. This makes an accurate advancement of the machine fully automatic even when the crib widths or distances between the track ties are irregular, and even without any intervention by an operator. All that is needed is to switch on the control system at the beginning of an operation and to switch it off at the end, all adjustments during the operation being fully automatically controlled, if desired.

In a preferred embodiment, an electrical control circuit connects the control element and the signal pulse generator to the recording instrument, and actuation of the control element by the selected track part produces an initiating control signal opening the circuit to the transmission of the signal pulses from the generator to the recording instrument. In this manner, the sum of the signal pulses being recorded at the instrument begins with each initiating control signal anew at zero. This avoids any errors being transferred into the next succeeding operation, thus adding up the errors. In the preferred embodiment of the present invention, any error will be limited to the one operating station, and the setting of the machine at the next station will be independent of such previous error.

The above and other objects, advantages and features of the present invention will become more apparent from the following detailed description of certain now preferred embodiments thereof, taken in conjunction with the accompanying drawing wherein

FIG. 1 is a schematic side view of a mobile track tamper incorporating one embodiment of this invention;

FIG. 2 is a similar partial side view of such a track tamper incorporating another embodiment of the invention;

FIG. 3 is an enlarged end view of a specific signal generator forming part of the invention, and of a control element associated therewith;

FIG. 4 diagrammatically shows the combination of two tamping units with different functions;

FIG. 5 diagrammatically illustrates a twin tamping unit for simultaneously tamping two adjacent ties;

FIGS. 6 to 8 show another embodiment of the invention incorporated into a mobile track tamper, FIG. 6 schematically illustrating the tamper while it advances from one tie to the next while FIGS. 7 and 8 schematically show other working positions of the tamper;

FIG. 9 is a schematic side view of a mobile machine for connecting and disconnecting tie fastening elements incorporating the present invention; and

FIG. 10 is a similar side view of a modified machine of this type.

In the drawing, like parts functioning in a like manner are designated by the same reference numerals in all figures.

Referring now to FIG. 1, a generally conventional mobile track tamper 1 is shown to comprise a frame mounted on running gears 2, 2 over a track including rails 4 fastened to ties 3. A track tamping unit 5 is mounted on a tamping tool carrier 6 which is vertically movably supported on the tamper frame, the reciprocating vibratory tamping tools of the tamping unit being arranged to tamp ballast under each tie. A hydraulic motor 7 is connected to the tamping tool carrier for vertically moving the same to place the tamping unit into and out of its operating position. The working direction of the tamper being indicated by the horizontal arrow, a brake 8 is shown associated with the rear wheels of the tamper for stopping the same intermittently while a selected tie is tamped. Furthermore, a hydraulically operated track jack 9 is mounted on the front end of the tamper frame, the jack including pairs of rail gripping rollers engaging the track rails. All of this structure is entirely conventional.

An odometer wheel 11 is mounted on the tamper frame and runs on a rail 4 to measure the distance covered by the tamper during its advance in the working direction, the odometer wheel being associated with an inductively operating signal pulse generator 12. The signal pulse generator is connected to an indicating instrument 13 on the tamper to transmit the generated pulse signals thereto, the indicating instrument comprising two indicators in the illustrated embodiment, the indicator 14 visibly showing the distance the tamper has advanced from the point when the pulsating control element 10 has signalled to the start of braking the advance of the tamper, and the indicator 15 visibly showing the distance the tamper has advanced from the signal point to the time the tamping tool carrier is lowered. The pulse signal generator 12 operates so that it generates a pulse signal for given equal distance units, for instance one signal for each centimeter or inch of advancement, so that the indicators will visibly show the total distance of advancement in such distance units.

The control element 10 is actuatable by selected parts of the track and, in the illustrated embodiment, is a pulsating element or pulsator. Pulsators are commercially available instruments which, in conjunction with other electrical circuit elements, include inductive coils which produce a pulsating circuit in the absence of metallic parts. If a metallic part or body comes close to the pulsator, the magnetic circuit thereof is influenced by turbulent flows so that the pulsation is discontinued and the circuit emits a control signal. Thus, the pulsating control element 10 is so mounted on the tamper frame that it will emit a control signal each time its magnetic circuit is interrupted by a metallic tie fastening element, such as a spike or a bolt. This produces the initiating signal for measuring the distance of advancement of the tamper, as hereinabove indicated.

In the illustrated embodiment, the pulsating control element 10 is mounted on the tamper frame about 50 cm or 20 inches ahead of the center line of the tamping unit 5. Thus, since the average width of a crib, i.e., the distance between two adjacent ties, is larger, i.e., about 65 cm or 26 inches, the pulsator 10 is positioned between two ties in a crib and is, therefore, not actuated by a tie fastening element when the tamper is in the tamping position shown in full lines in FIG. 1.

The tamper operates as follows:

After a selected tie has been tamped, the tamping tool carrier 6 is raised by hydraulic motor 7 and, in a known manner, a limit switch is actuated automatically to advance the tamper (see, for instance, U.S. Pat. No. 2,976,816, dated Mar. 28, 1961, and U.S. Pat. No. 3,127,848, dated Apr. 7, 1964). While this advancement causes the pulse generator 12 to transmit signal pulses corresponding to the distance units measured by odometer 11 over electric circuit line 16 connecting the pulse generator 12 to the indicating instrument 13, a circuit breaker in line 16 prevents the signal pulses from being received by the instrument so that the advance is not indicated.

However, when the tamper is in the position (indicated in FIG. 1 in broken lines) when the pulsator 10 is in vertical alignment with a tie 3, the metallic tie fastening element will cause the pulsator to emit an initiating control signal which is transmitted by electric circuit line 17 to the circuit breaker to move the same into inoperative position, thus opening the line 16 to the indicating instrument. From this moment on, the signal pulses from signal pulse generator 12 are received so that the distance of advancement beyond this point is visibly shown on indicators 14 and 15.

The indicator 14 is connected to the brake 8 by electric circuit line 19 which includes a relay. When a predetermined distance of advancement has been shown on the indicator 14, the indicator actuates the relay in line 19 to operate the brake. In the illustrated embodiment, this predetermined distance is 20 cm or 8 inches but this distance may be adjusted to any desired value, depending primarily on the width of the cribs, by means of an adjustment element 18. In the illustrated embodiment, it takes the hydraulic brake about 30 cm or 12 inches to bring the tamper to a complete stop, the entire distance of the tamper advancement since the initiating signal was emitted from pulsator 10 being visibly shown on indicator 15. This predetermined distance may also be adjusted to a desired value by adjustment element 20, such adjustment also taking into account the time required for lowering the tamping tool carrier 6 upon stoppage of the tamper. The electric circuit lines 21 connects the indicator 15 to the hydraulic motor 7 so that the same will lower the tamping tools into operating position in the ballast when the indicator 15 has shown the pre-set value.

Compared to the control of the tamper advancement and lowering of the tamper unit solely in response to the measured distance of tamper advance, this arrangement has the considerable advantage that any errors occurring at any one intermittent working stage are not accumulated from one stage to the next. Rather, if such an error occurs at one stage so that the tamping unit is not perfectly centered over a tie to be tamped at that stage, this error does not influence the advancement of the tamper during the following stage because each measurement of the advancement distance begins anew at zero. Furthermore, the tamper operator can read any error from the pre-set values on the indicators so that he has the opportunity to correct such errors by manual operation of the controls.

It would also be possible to automate such corrections by the use of a control device, which may be connected to the indicating instrument or used instead of it, such control device computing any deviations from pre-set values and automatically controlling the speed, braking, etc., in response to such computations, similarly to the manner described hereinbelow in conjunction with the embodiment of FIGS. 2 and 3.

In this embodiment, the pulsator 10 is centrally arranged in respect of the tamping unit 5, i.e., it is mounted on the tamper frame intermediate the two tamping tools so that it is in vertical alignment with the tie being tamped thereby. As more fully shown in FIG. 3, the pulsator 10 is mounted on an axle 22 which also carries an odometer wheel 23 which is in rolling contact with a rail 4. A signal pulse generator 24 is connected to the odometer wheel and generates signal pulses in response to distance units measured thereby. The magnetic circuit of the pulsator is indicated in broken lines in FIG. 3, its actuation by tie fastening bolt 25 being clearly illustrated.

An electric circuit line connects the signal pulse generator 24 to indicating instrument 26 to transmit the generated signal pulses thereto. The indicating instrument has a first visible scale 27 for showing deviations from the normal crib width, i.e., distance between adjacent ties, at the right rail, a second visible scale 28 for showing the distance of tamper advancement along the right rail, a third visible scale 29 for showing deviations from the normal crib width at the left rail, and a fourth visible scale 30 for showing the distance of tamper advancement along the left rail. A totalizer 33 is connected to the indicating instrument to compute any deviations shown on scales 27 and 29 and, in response to such computations, automatically to adjust the speed of the forward movement of the tamper and/or to initiate braking by means of the block 34 of relays in the control circuits actuating the tamper and brake movements.

In this embodiment, the indicating instrument 26 shows the distance traveled by the tamper from the beginning of the tamper movement, the indicators showing the deviations of the positions of the ties from the norm. These recorded deviations are used for the automatic control of the machine.

It is possible, of course, to compute a mean value between the deviations at the left and right rail, and to use this mean value for the automatic control of the machine movement. In this case, any error is cut in half at each rail in case the tie is obliquely positioned in relation to the rails rather than correctly extending perpendicularly thereto. In this manner, an effective automatic control can be achieved at obliquely positioned ties, particularly with the embodiment of FIG. 1 wherein the pulsating control element 10 is mounted ahead of such ties.

While visibly indicating instruments have been illustrated because of their advantage in permitting an operator to make ready adjustments upon reading the indication of the distances traveled by the tamper, it is fully within the scope of the present invention to replace these instruments by simple recording devices, the recorded values being used for the control of the tamper movement.

FIG. 4 shows that the controls of this invention may also be effectively used in tampers combining a first tamping unit 5 arranged to tamp ballast under a tie and a second tamping unit 35 arranged to tamp the ballast in the crib between two ties, such as shown in U.S. Pat. NO. 3,111,909, dated Nov. 26, 1963. In this embodiment, the arrangement of FIG. 1 is duplicated for the surface vibratory tamper 35, i.e., its lowering into the tamping position is also controlled by a pulsator 10 emitting its initiating control signal which is transmitted to a circuit breaker in the electrical circuit line feeding the pulse signals from pulse generator 12 to indicating or recording instruments 13, 13, a single pulse generator being provided for both instruments.

In FIG. 5, the invention is applied to the operation of a tamper having a twin tamping unit comprising two commonly driven tamping tool assemblies 36, 37 for tamping two adjacent ties simultaneously, such as shown in U. S. Pat. No. 3,357,366, dated Dec. 12, 1967. In this case, the pulsator 10 is spaced ahead of the twin tamping unit in the operating direction of the tamper by twice the width of the cribs, measured from the center of the tamping unit. The control operates in the same manner as described in connection with FIG. 1.

In the embodiment of FIGS. 6 to 8, the control element is not a pulsator but a wheel 38 which is pivotally mounted on the tamper frame to run on the ballast next to rail 4. As clearly shown in FIG. 6, the freely pivotally mounted wheel 38 will be lifted by the ties 3 as the wheel moves into contact therewith, the raising of the wheel operating a switch to produce an initiating control signal. At the same time, wheel 38 operates the signal pulse generator 39 so that the same begins to emit a series of signal pulses corresponding to the distance units (centimeters or inches) traveled by the tamper.

FIG. 6 shows the tamper in the position when it has moved 40 cm since the tamping unit 5 was in the lowered tamping position. FIG. 7 shows the rear portion of the tamper after the tamper has advanced 45 cm from the last preceding tamping position, at which point brake actuation is initiated. FIG. 8 shows the front portion of the tamper after it has advanced 65 cm to the next tamping position wherein the tamping unit 5 is lowered again.

As in the embodiments of FIGS. 1 and 2, here, too, the tamper will automatically move forward as the tamping tool carrier 6 is raised out of the ballast, the signal pulse generator 39 transmitting signal pulses to indicating or recording instrument 40 to show the number of centimeters or inches the tamper is advancing.

The adjustment element 41 has set the instrument 40 to the desired distance of tamper advancement before the brake 8 is to be operated (45 cm in the illustrated embodiment), and the adjustment element 42 has set the desired distance before the tamping tool carrier 6 is to be lowered (65 cm in the illustrated embodiment) so that the stopping of the tamper and the positioning of the tamping unit is correspondingly controlled. Just about after the tamper has moved to the position wherein the tamping unit is immersed in the ballast, the control wheel 38 runs up the edge of an adjacent tie to emit the control signal which returns the instrument setting to zero to start the next control stage. It may be desirable to delay this zero setting somewhat so that an operator has the opportunity to correct the setting of the indicating instrument 40 in such cases where the crib width is narrower than the norm and the control wheel 38, therefore, is lifted prematurely to emit a faulty control signal.

It will be obvious from the above description that the control of the tamper movement along the track is very precise, which makes the present invention particularly useful in track maintenance work requiring much more accurate maintenance of exact distances between successive operating stations as is needed in track tamping. For instance, spike pullers or drivers, or wrenches for tie bolts mounted on mobile carriages running on the track must be precisely aligned with the tie fastening element on which they work, as the carriage moves from tie to tie.

FIGS. 9 and 10 schematically show machines of this general type, the machine illustrated in FIG. 9 being designed for assembling and disassembling rail attachment means 43, which may include tie plates, bolts and nuts, such means being used to fasten the rails 4 to ties 3. Machines of this general type are more fully described and claimed, for instance, in simultaneously filed applications Ser. Nos. 97,707 and 97,796, now U.S. Pat. Nos. 3,690,264, dated Sept. 12, 1972, and 3,722,423, dated Mar. 27, 1973, and respectively entitled "Mobile Track Working Apparatus" and "Mobile Ballast Treating and Rail Fastening Element Engaging Tool," of which the joint inventor Josef Theurer is also a joint inventor.

This machine comprises a frame 45 which moves on running wheels 44, the underside of the chassis or frame 45 carrying the tools 46, 47 and 48. The tool 46 serves to drive the tie bolts, the tool 47 serves to place or remove the tie plates, and the tool 48 serves to fasten or unfasten the nuts, the arrows 49, 50 indicating the operating directions during assembly and disassembly, respectively, of the rail attachment means 43. The tools may be hydraulically driven, the required flow of hydraulic fluid from common fluid storage 51 being controlled from panel 52 which is mounted in an operating stand 53 which is also carried on the underside of the chassis. As more fully disclosed in the above-cited patent applications, the working tools 46, 47 and 48 are movable in relation to each other and in relation to the carriage 45 in the direction of track elongation.

To control the positioning of each tool in respect of a rail attachment means 43 precisely and automatically, a control element 54 is associated with each tool. As more fully described in connection with FIG. 1 or FIG. 6, for instance, the control element is arranged to emit an initiating control signal when activated by a track part, such as attachment means 43, an odometer wheel 55a cooperating with a signal pulse generator 55 to produce signal pulses corresponding to distance units traveled by the associated tool. These signal pulses are transmitted to an indicating or recording instrument 56 at the operating stand 53 to enable the movement of the associated tool to be accurately and automatically controlled in response to the signal pulses and according to the setting of instrument 56 in a manner identical with that described hereinabove in connection with the tamper movement control.

The machine of FIG. 10 also carries three tools mounted in series but, in this case, all three tools are power wrenches 48', each of which is controlled by associated control element 54, pulse generator 55 and odometer wheel 55a. In this modification, the tools for working on the tie plates and bolts are mounted on other portions of the chassis 45. In such an arrangement, the efficiency of the wrenches can be practically tripled, which is of particular advantage when the machine is used in connection with the replacement of old track by new track.

Many variations and modifications of the illustrated embodiments will readily occur to those skilled in the art, particularly after benefiting from the present teaching, without departing from the spirit and scope of the present invention which is defined in the claims.

Claims

We claim:

1. A mobile track working machine carrying tool means for working at spaced consecutive operating stations along a track comprises of rails fastened to ties, the machine comprising

1. a pulsator actuatable by consecutive track parts for intermittently producing an initiating control signal,

2. a control means for intermittently controlling the advancement of the machine from station to station, the control means including a control element measuring units of distance traversed by the machine and a signal pulse generator producing signal pulses indicating said distance, and

3. a signal pulse recording instrument connected to the generator and receiving signal pulses therefrom in response to the intermittent initiating control signals from the control.

2. A mobile track working machine carrying tool means vertically movably mounted on the machine for working at spaced consecutive operating stations along a track comprised of rails fastened to ties, the machine comprising

1. a control means actuatable by consecutive track parts for intermittently controlling the advancement of the machine from station to station and for controlling the lowering of the tool means into a working position upon actuation of the control means by the consecutive track parts, the control means including a signal pulse generator producing pulses indicating the distance of each of the intermittent advancements, and

2. a signal pulse recording instrument connected to the generator and receiving the signal pulses therefrom upon actuation of the control means by the consecutive track parts.

3. The mobile machine of claim 2, wherein the control means comprises an element mounted on the machine ahead of the working tool means in the working direction of the machine.

4. The mobile machine of claim 3, wherein the distance of the control means element from the working tool means is smaller than the smallest crib width.

5. The mobile machine of claim 2, wherein the control means comprises a pulsator fixedly mounted on an axle extending from the machine, an odometer wheel running on one of the track rails being carried by the axle, and the signal pulse generator being associated with the odometer wheel whereby each of the signal pulses corresponds to a distance unit measured by the odometer wheel.

6. The mobile machine of claim 2, wherein the tool means is a tamping unit, said machine being a mobile tamper.

7. The mobile machine of claim 2, wherein the tool means is a tool for assembling and disassembling rail attachment means.

8. The mobile machine of claim 7, wherein a series of said tools are movably mounted on a frame, each tool constituting said mobile machine.

9. A mobile track working machine carrying tool means for working at spaced consecutive operating stations along a track comprised of rails fastened to ties, the machine comprising

1. a control means actuatable by consecutive track parts for intermittently controlling the advancement of the machine from station to station, the control means including a signal pulse generator producing signal pulses indicating the distance of each of the intermittent advancements, and

2. a signal pulse recording instrument connected to the generator and receiving the signal pulses therefrom upon actuation of the control means by the consecutive track parts, the recording instrument visibly indicating the number of the received signal pulses.

10. The mobile machine of claim 9, wherein rotary wheel means is provided for mesasuring units of distance traversed by the machine, each of the signal pulses corresponding to a measured distance unit.

11. A mobile track working machine carrying tool means for working at spaced consecutive operating stations along a track comprised of rails fastened to ties, the machine comprising

1. a control means actuatable by consecutive track parts for intermittently controlling the advancement of the machine from station to station, the control means including a signal pulse generator producing signal pulses indicating the distance of each of the intermittent advancements,

2. a signal pulse recording instrument connected to the generator and receiving the signal pulses therefrom upon actuation of the control means by the consecutive parts, and

3. an electrical control circuit connecting the signal pulse generator to the recording instrument, actuation of the control means by the consecutive track parts producing an initiating control signal opening the circuit to the transmission of the signal pulses from the generator to the recording instrument, the sum of the signal pulses being recorded at the instrument beginning with each initiating control signal.

12. A mobile track working machine carrying tool means vertically movably mounted on the machine for working at spaced consecutive operating stations along a track comprised of rails fastened to ties, the machine comprising

1. a control means actuatable by consecutive track parts for intermittently controlling the advancement of the machine from station to station, the control means including a signal pulse generator producing signal pulses indicating the distance of each of the intermittent advancements, and

2. a signal pulse recording instrument connected to the generator and receiving the signal pulses therefrom upon actuation of the control means by the consecutive track parts, the recording instrument controlling the lowering of the tool means into a working position upon recordal of a set number of the signal pulses received upon actuation of the control means by the consecutive track parts.

13. A mobile track working machine carrying tool means vertically movably mounted on the machine for working at spaced consecutive operating stations along a track comprised of rails fastened to ties, the machine comprising

1. a control means actuatable by consecutive track parts for intermittently controlling the advancement of the machine from station to station, the control means including a signal pulse generator producing signal pulse indicating the distance of each of the intermittent advancements,

2. a signal pulse recording instrument connected to the generator and receiving the signal pulses therefrom upon actuation of the control means by the consecutive track parts, and

3. a brake means for stopping the machine at the operating stations, actuation of the control means by the consecutive track parts, producing an initiating control signal, and the recording instrument being arranged to indicate the signal pulses received from the time of the control signal to the beginning of the brake means actuation as well as the signal pulses received from the time of the control signal to the lowering of the tool means into a working position.

14. A mobile track working machine carrying tool means for working at spaced consecutive operating stations along a track comprised of rails fastened to ties, the machine comprising

1. a control means actuatable by consecutive track parts for intermittently controlling the advancement of the machine from station to station, the control means including a signal pulse generator producing signal pulses indicating the distance of each of the intermittent advancements, and

2. a signal pulse recording instrument connected to the generator and receiving the signal pulses therefrom upon actuation of the control means by the consecutive track parts, the recording instrument being arranged to indicate deviations of actual tie spacings from a set norm.

15. A mobile track working machine carrying tool means for working at spaced consecutive operating stations along a track comprised of rails fastened to ties, the machine comprising

1. a control means actuatable by consecutive track parts for intermittently controlling the advancement of the machine from station to station, the control means including a signal pulse generator producing signal pulses indicating the distance of each of the intermittent advancements,

2. a signal pulse recording instrument connected to the generator and receiving the signal pulses therefrom upon actuation of the control means by the consecutive parts, and

3. computer control means for controlling the advancement of the machine from station to station in response to the recorded deviations from a set norm computed in said computer control means.

16. The mobile machine of claim 15, wherein the computer control means is connected in series with the recording instrument and receives the recorded deviations therefrom, the computer control means including a totalizer and a relay-operated control for operating means regulating the advancement of the machine.

17. A mobile track working machine carrying tool means for working at spaced consecutive operating stations along a track comprised of rails fastened to ties, the machine comprising

1. a control means associated with each rail of the track and actuatable by consecutive track parts for intermittently controlling the advancement of the machine from station to station, each control means including a signal pulse generator producing signal pulses indicating the distance of each of the intermittent advancements, and

2. a signal pulse recording instrument connected to the generator and receiving the signal pulses therefrom upon actuation of the control means by the consecutive track parts.

18. The mobile machine of claim 17, wherein the signal pulse recording instrument is connected to both generators to receive the signal pulses therefrom, a control means being connected in series to the recording instrument and receiving therefrom a mean value of the signal pulses received from both generators, the mean value controlling the advancement of the machine.

19. A mobile track working machine carrying tool means for working at spaced consecutive operating stations along a track comprised of rails fastened to ties, the machine comprising

1 a control means actuatable by consecutive track parts for intermittently controlling the advancement of the machine from station to station, the control means including a signal pulse generator producing signal pulses indicating the distance of each of the intermittent advancements,

a. the control means comprising a wheel pivotally mounted on the machine and running laterally adjacent the rail, consecutive ones of the ties lifting the pivotally mounted wheel upon contact of the wheel with respective ones of the ties, and each lifting of the wheel causing an initiating control signal to be emitted, the signal pulse generator being coupled to the control wheel, and

2. a signal pulse recording instrument connected to the generator and receiving the signal pulses therefrom upon actuation of the control means by the consecutive track parts.

20. A mobile track working machine carrying tool means for working at spaced consecutive operating stations along a track comprised of rails fastened to ties, the machine comprising

1. a control means actuatable by consecutive track parts for intermittently controlling the advancement of the machine from station to station, the control means including a signal pulse generator producing signal pulses indicating the distance of each of the intermittent advancements,

a. the control means comprising a pulsator having an electric circuit transmitting an initiating control signal upon alignment with the consecutive track parts, and

2. a signal pulse recording instrument connected to the generator and receiving the signal pulses therefrom upon actuation of the control means by the consecutive track parts.