Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
180 words
1) An apparatus for wrapping loads in stretchable film comprising a pre-stretching unit (7) which is translated in a circular path around the periphery of a load (10) to be wrapped, whilst being reciprocated with respect to the height of said load (10), said unit comprising a supply reel (18) for the stretchable film, a first pair of nipple rollers (21-22) positively driven at a first peripheral speed by a suitable motor, and a second pair of nipple rollers (35-36) driven at a second peripheral speed greater than the said first peripheral speed, by the said driving motor, through a suitable transmission, and in which the said film from said supply reel is passed through the said two pairs of nipple rollers (21,22-35,36) for being pre-stretched before being wound around the said load (10), characterized by the fact that the output from the said motor is transmitted through a reducer (37) to one pair of the said nipple rollers, and is transmitted to the other pair of nipple rollers from said reducer (37) through a suitable speed change gear (26).
Claim 2
Dependent Claim
180 words
1) An apparatus for wrapping loads in stretchable film comprising a pre-stretching unit (7) which is translated in a circular path around the periphery of a load (10) to be wrapped, whilst being reciprocated with respect to the height of said load (10), said unit comprising a supply reel (18) for the stretchable film, a first pair of nipple rollers (21-22) positively driven at a first peripheral speed by a suitable motor, and a second pair of nipple rollers (35-36) driven at a second peripheral speed greater than the said first peripheral speed, by the said driving motor, through a suitable transmission, and in which the said film from said supply reel is passed through the said two pairs of nipple rollers (21,22-35,36) for being pre-stretched before being wound around the said load (10), characterized by the fact that the output from the said motor is transmitted through a reducer (37) to one pair of the said nipple rollers, and is transmitted to the other pair of nipple rollers from said reducer (37) through a suitable speed change gear (26).
Claim 3
Dependent Claim
35 words
2) Apparatus according to claim 1, characterized by the fact that the said speed change gear (26) is disposed in the transmission line between the motor-reducer (37) and said first pair of nipple rollers (21,22).
Claim 4
Dependent Claim
70 words
3) Apparatus according to claim 1, characterized by the fact that means (65-66) are provided which are responsive to the tension imposed to the pre-stretched web (118) being delivered to the load (10) to be wrapped, the said tension-responsive means (65,66) acting on control means (69, 69′, 69") electrically connected to a circuit (79) which is apt to control the rotational speed of the said nipple-rollers (21,22-35,36) driving motor (37).
Claim 5
Dependent Claim
48 words
4) Apparatus according to claim 3, in which the said tension responsive means are in the form of dandy rollers (65,66), the said dandy rollers having associated therewith abutment means (67,68) cooperating with two or more sensors (69, 69′,69") electrically connected to the said motor speed-control circuit (79).
Claim 6
Dependent Claim
55 words
5) Apparatus according to any one of the preceding claims, characterized by the fact that the said stretchable film supply reel (18) is positively driven at the same peripheral speed of the said first nipple-rollers pair (21, 22), by frictional contact with one (21) of the said nipple rollers of said first nipple rollers pair.
Claim 7
Dependent Claim
28 words
6) Apparatus according to claims 2 or 3, in which means (51,52,53,55,56) are provided for adjusting the tension value to which the said tension-responsive means (65,66) are responsive.