counter 15 exceeds the acceptable stitch number predetermined by the latch circuit 10 the range between u03b1 and u03b2 shown by i in fig2 the comparator circuit 12 outputs l signal the nand circuit 6 thereby outputs h signal which in turn causes the and circuit 7 to open when the sewing is finished and the operator then steps on the pedal of the sewing machine to cut the thread the thread cutting generation circuit 18 outputs h level thread cutting signal which is then given to the output circuit 26 through the and circuit 7 the output circuit 26 thereby inputs 1 as the number of the works sewn to the counter not shown of the monitor unit for the following sewings whenever the sewing is finished 1 is automatically inputted to the counter of the monitor unit in the same manner as described above so that the total number of the works sewn is automatically counted in the event in the sewing of a second or after piece of a product that a thread break takes place by some external factor outside the acceptable stitch number range i in fig 2 as shown by ii in fig2 i e in the course of sewing and a thread cutting signal is generated by operating a pedal an operation of the present invention is conducted in this case the thread cutting signal.