modules being identical the economy in construction and maintenance which results therefrom is very considerable the various mechanisms thus aligned on the beam 1 are separated from one another by partitions 65 which play the role of stiffeners and which confer on the beam 1 a rigidity all the greater as the mechanisms which act on it are more numerous the invention preserves all its advantages in its application to an under striking felting machine fig1 and 13 in this case the beam 1 is situated in bottom position and the crank rod units 7a and 7b are again as easily accessible through the front or through the rear of the machine the underneath striking can be produced by two boards 6a 6b fig1 or by a single board 6 fig1 two types of strike can besides be combined fig1 there are then provided two beams 1 and 1a one above the other beneath which bear respectively units 7a 7b actuating two upper boards 6a 6b and units 70a 70b actuating two lower boards 60a 60b all these crank rod units are also perfectly accessible through the front and through the rear it is also possible to combine the two types of strike no longer simultaneously but successively fig1 the felting machine is then in practice split into two half machines traversed successively by the fabric 4 one beam 1 is in upper position and one beam 1a is in lower position the end units 7b and 70b are directly accessible through the front and through the rear respectively as to.