Alert system in a mobile track surfacing machine

In a mobile track surfacing machine arranged for intermittent advancement by selected distances along the track from one tamping station to a succeeding tamping station, the track including a plurality of successive ties arranged on ballast and defining cribs therebetween, and the machine carrying a track tie tamping unit having tamping tool means immersible in respective ones of the cribs at a respective one of the tamping stations and an operator's station arranged within view of the tamping unit, the operator's station including a control panel for enabling the operator to operate the machine:

• apparatus for alerting the operator to an approach to the succeeding tamping station as the machine advances thereto, and for enabling the operator to center the tamping tool means between the successive ties at the succeeding tamping station, the apparatus comprising the combination of
• (a) a means for defining the selected distances,
• (b) a spraying nozzle mounted on the machine close to the surface of the ballast and arranged to produce a relatively small colored marker of a size of the order of about two to three ballast pieces in a respective one of the cribs,
• (c) a signal means at the operator's station within view of the operator for generating a progressively changing acoustic alert signal audibly indicating to the operator an approach to the succeeding tamping station during the advancement of the machine and including a final signal indicating the succeeding tamping station, and
• (d) means for controlling the spraying nozzle for producing successive ones of the colored markers and for controlling the signal means for generating the progressively changing acoustic alert signal,
• (1) the controlling means operatively connecting the distance defining means, the spraying nozzle and the signal means in response to a selected distance defined by the means for defining the selected distances whereby the progressively changing alert signal audibly indicates to the operator the approach to the succeeding tamping station as the advancing machine approaches the succeeding tamping station, the final signal indicates to the operator the arrival at the succeeding tamping station and the colored marker enables the operator to center the tamping tool means.

A method of alerting an operator of a mobile track surfacing machine arranged for intermittent advancement by selected distances along the track from one tamping station to a succeeding tamping station, the track including a plurality of successive ties arranged on ballast and defining cribs therebetween, and the machine carrying a track tie tamping unit having tamping tool means immersible in respective ones of the cribs at a respective one of the tamping stations and an operator's station including a control panel for enabling the operator to operate the machine, which comprises the steps of

• (a) defining each one of the selected distances from the tamping tools means to the succeeding tamping station adjacent the succeeding tamping station,
• (b) generating a control signal in response to each of the selected distances,
• (c) generating a progressively changing alert signal including a final signal readily perceptible by the operator in response to the control signal whereby the operator is alerted to an approach to the succeeding tamping station as the advancing machine approaches the succeeding tamping station and the arrival at the succeeding tamping station at the final signal,
• (d) applying a colored marker in a respective one of the cribs in response to the control signal;
• and
• (e) controlling the position of the tamping unit in the succeeding tamping station under the guidance of the colored marker in the respective crib to center the tamping tool means between the successive ties at the succeeding tamping station.