or 18 by means of set bolts 22 the inner surface of the stop ring 20 which faces the recessed portion 19 formed on the can transporting arm 14 15 16 17 or 18 has two projections 23 which are diametrically located as illustrated in fig5 and 6 and which engage with the recessed portion 19 as illustrated in fig5 in the above described embodiment some of the positions of the stop rings 20 are set by means of the set bolts 22 so that when the can transporting arm 14 illustrated at the left in fig1 is in a vertically downward position as illustrated by a solid line in fig5 the projections 23 formed on the stop rings 20 become abutted with upper and lower side walls 19a of the recessed portion 19 as illustrated in fig5 as a result when the traverse bar 10 is rotated clockwise by an angle u03b1 which is usually 90 degrees the projections 23 press against the side walls 19a of the recessed portion 19 and accordingly the can transporting arm 14 is swung clockwise in fig5 by an angle u03b8 which is equal to u03b1 i e usually 90 degrees and is brought to a horizontal position which is illustrated by a two dot and dash line in fig5 furthermore in the above described embodiment of the present invention the remaining stop rings 20 are secured to the traverse bar 10 or 11 so that when the can transporting arms 15 through 18 illustrated in fig1 are positioned vertically downward as illustrated by a solid line in fig6 the projections 23 of the stop rings 20 are located at positions which are distant from the side walls 19a of the recessed portion 19 by an angle u03b2 u03b4 u03b2 which is.