Method and apparatus for monitoring wear of a continuous chain

A method for monitoring wear of a continuous chain having a plurality of links successively connected comprising the steps of:

• spacedly positioning a pair of sensors along said chain wherein said sensors generate signals by sensing the presence and absence of each of said links;
• calculating a first time interval between actuation of said pair of sensors when sensing the presence of each of said links;
• counting a second time interval for said chain to travel between common locations on successive links past one of said pair of sensors;
• calculating a time ratio of said first time interval over said second time interval;
• inputting a predetermined chain pitch value wherein said chain pitch is the linear distance between common locations on successive chain links;
• and
• calculating chain stretch by multiplying said chain pitch by said time ratio to provide a linear distance by which said chain has lengthened between said pair of sensors.

A method for monitoring wear of a continuous chain having a plurality of links successively connected comprising the steps of:

• positioning a pair of photoelectric sensors along and adjacent said chain wherein said photoelectric sensors are independently actuated by sensing the presence and absence of each of said links;
• calculating an initial time interval between the actuation of said photoelectric sensors when said chain stretch is zero;
• calculating a first time interval between the actuation of said pair of photoelectric sensors when sensing the presence of each of said links;
• counting a second time interval for said chain to travel between common locations on successive links past one of said pair of photoelectric sensors;
• calculating a time ratio of said first time interval less said initial time interval over said second time interval wherein said time ratio is continuously calculated throughout said entire continuous chain to provide an output indicative of chain wear of any portion of said chain;
• and
• providing an indicator when said time ratio exceeds a predetermined value.

A method for monitoring wear of a continuous chain having a plurality of links successively connected comprising the steps of:

• positioning a pair of photoelectric sensors along and adjacent said chain wherein said photoelectric sensors are independently actuated by sensing the presence and absence of said links;
• calculating an initial time interval between the actuation of said photoelectric sensors when said chain stretch is zero;
• calculating a first time interval between the actuation of said pair of photoelectric sensors when sensing the presence of each of said links;
• counting a second time interval for said chain to travel between common locations on successive links past one of said pair of photoelectric sensors;
• calculating a time ratio of said first time interval less said initial time interval over said second time interval;
• providing an indicator when said time ratio exceeds a predetermined value;
• inputting a predetermined chain pitch value wherein said chain pitch is the linear distance between common locations on successive chain links;
• and
• calculating chain stretch by multiplying said chain pitch by said time ratio to provide a linear distance by which said chain has lengthened between said pair of photoelectric sensors due to said chain wearing.

A method comprising the steps of:

• positioning a pair of photoelectric sensors along and adjacent said chain wherein said photoelectric sensors are independently actuated by sensing the presence and absence of said links;
• calculating an initial time interval between the actuation of said photoelectric sensors when said chain stretch is zero;
• calculating a first time interval between the actuation of said pair of photoelectric sensors when sensing the presence of said links;
• counting a second time interval for said chain to travel between common locations on successive links past one of said pair of photoelectric sensors;
• calculating a time ratio of said first time interval less said initial time interval over said second time interval;
• providing an indicator when said time ratio exceeds a predetermined value;
• inputting a predetermined range of desired values for instantaneous chain speed;
• and
• providing an indicator when said instantaneous chain speed extends outside of said predetermined range of desired values for said instantaneous chain speed.

The method for monitoring wear of a continuous chain having links spacedly connected comprising the steps of:

• spacedly positioning a pair of photoelectric sensors at fixed locations along said chain at a predetermined distance wherein said sensors are positioned at common locations with respect to said links so that said photoelectric sensors are simultaneously actuated between a first state, wherein the presence of said links are sensed by said photoelectric sensors, and a second state, wherein the absence of said links are sensed by said sensors, when said chain stretch is zero;
• calculating a first time interval between actuation of said photoelectric sensors into said first state when said chain begins to lengthen by wearing;
• timing a second interval for said chain to travel between common locations on successive links past one of said pair of photoelectric sensors;
• inputting a predetermined chain pitch value wherein said chain pitch is the linear distance between common locations on successive links of said chain;
• calculating chain stretch by dividing said first time interval by said second time interval and multiplying by said chain pitch;
• inputting a predetermined value for said chain stretch;
• and
• providing an indicator when said chain stretch exceeds said predetermined value for said chain stretch.

An apparatus for monitoring the wear of a continuous chain having a plurality of links successively connected comprising:

• first and second means, spacedly positioned along said chain, for sensing the presence of each of said links;
• means for processing the signals generated by said sensors to calculate the necessary time intervals for providing an output indicative of said chain wear wherein said signals are continually generated and processed for each of said links throughout said entire continuous chain to provide an output indicative of chain wear of any portion of said chain;
• and
• means for indicating when said output exceeds a predetermined value.

An apparatus for monitoring the wear of a continuous chain having a plurality of links successively connected comprising:

• first and second means, spacedly positioned along said chain, for sensing the presence of said links;
• means for processing the signals generated by said sensors to calculate the necessary time intervals for providing an output indicative of chain wear;
• means for indicating when said output exceeds a predetermined value;
• means for inputting a predetermined chain pitch value wherein said chain pitch value is the linear distance between common locations on successive links;
• and
• means for calculating chain stretch by multiplying said chain pitch by said time ratio to provide a linear distance by which said chain has lengthened between said first and second sensing means due to said chain wearing.