FLYING SHEARS

Abstract: Guillotine shearing machine, especially for cutting continuous metal bands (90), in which each of the two longitudinal blades (15), (16) counterpoised by means of connections to connecting rods (39), (40), (41), (42) each supported by a pair of cranks (31-32), (35-36) and (33-34), (37-38), translates, both parallel to each other, on equal circular trajectories in such a way that one blade (15) encountering the other (16) in proximity to the cutting plane and progressively superimposing each other, effects the cut, speed of the blades (15), (16) in each cycle being regulated according to the sliding speed of the band (90) so that in the zone of contact the speed of the blades (15), (16) coincides with that of the band (90) enabling pieces of band to be cut off in whatever length is desired.

Description: FLYING SHEARS The so-named guillotine shearing machine is a well-known 5 tool. One blade, generally the upper one, is mobile and slides on runners which keep the movement rectilinear and transversal to the cutting plane. The blade is operated by cams or by hydraulic systems. 0 Shearing machines used for cutting lengths of sheet metal, profiles, continuous moving bands, comprise a pair of drums between which the band passes, and radially set blades which meet at the shearing plane to cut through the moving piece. The radial position of the blades obviously determines the 5 angle they assume, which angle varies progressively during cutting. This means that the advantages of speed and simplicity in .. continuously cutting a moving band are to some extent ad¬ versely affected and the operation lacks that precision 0 which can only be obtained with blades set perfectly per¬ pendicular to the piece to be cut. -- The invention here described avoids these drawbacks at the same time offering considerable advantages as will now be explained. 5 Subject of the invention is a guillotine shearing machine, especi4lly one for cutting continuous metal bands, wherein the opposing longitudinal blades translate parallel one to another along equal circular trajectories with parallel axes of rotation lying on the same geometrical plane. Blade movement is reciprocally synthronized. The phases in movement of one blade in relation to the other are such that one blade meets the other close to the shear¬ ing plane becoming progressively superimposed to make the cut. 5 The start of each cutting cycle, corresponding to a 360° rotation of the blades, is controlled in relation to cer¬ tain speeds at which the b.and, or any other piece to be cut, and the blades move -during the cycle, and at the most suitable instant for cutting off the desired length of band. Blade speed is adjusted according to that of the band to be cut in such a way that, when the cut is made, the speed of the cutting edge practically coincides with that of band movemen . The blade is moved by means of a double pair of cranks for each of the two blades, one pair being situated at each end of the blade. The two cranks in each pair are connected by sprocket wheels with an idling sprocket wheel in between them. The pairs of cranks at each end of the blade are connected by a longitudinal shaft to ensure synchronized movement, preferably by pairs of gears. The drive shaft is preferably fixed to the upper crank of the lower blade, connected to the lower crank of the upper blade by a pair of sprocket wheels. Synchronizing shafts between the pairs of cranks for each blade are respectively connected, by means of gears, to the sprocket wheel fixed to the upper crank of the lower blade, and to the sprocket wheel fixed to the lower crank of the upper blade. Each blade is fixed at either end to two connecting rods respectively connected to the cranks forming either of the pairs that support each of the above blades at both ends. The connecting rods of the '.upper blade support an elastic presser acting over the whole width of the translating band, at the moment when ' the blades meet, accompanying their move ment .and at the same time stabilizing their vertical posi¬ tion to hold the b.and relatively steady in relation to the "blades that make the cut. The start of each shearing cycle to cut off the desired length of band, in each cycle, as well as regulation of blade rotation speed, in each cycle, according to the speed at which the band moves so that blade and band speeds shall be equal when the blade makes contact with the band, is op- erated automatically by an electronic control panel which memorizes the information received from sensors applied to the band and which, according to the speed of band movement and according to a program typed in on a keyboard or by some other means, has one or more shearing cycles carried out for cutting off one or more equal or different lengths of band, as desired. The characteristics and purposes of the invention will be made still clearer by the following examples of its execu¬ tion illustrated by drawings. Fig. 1 Guillotine shearing machine, sub eqt of the inven¬ tion, seen from the front. Fig. 2 The same machine seen from the back. Fig. 3 Cross section view of the same machine. Fig. 4 Diagram to show blade movements. The shearing machine, subject of the invention, comprises a base (10) and uprights (11), (12) connected at the top by the head (43) . Each upright comprises in turn the side pieces (13), (14). The upper (15) .and lower (16) longitudinal blades are res_ spectively supported by frames (17), (18), the upper one comprises the bushings (19)-20) and the lower one compri¬ ses the bushings (23-26) . Said bushings house the rotatable pins (27), (28) and (29), (30) of the cranks (31), (32) and (33), (34) which deter- mine the cutting movement of the blades. The extremities of the frames (17) and (18) create a kind of connecting rod (39), (40) and (41), (42) for respective ly connecting the pairs of cranks (31-32), (33-34), (35-36) (37-38). The drive shaft (50) is fixed to the crank (33). and can rotate on the bearings (51), (52) mounted respectively on the sides (13) and (14) of the upright (11). By means of the sprocket wheel (53) and the opposing sproc_ 5 ket wheel (54), said shaft is similarly fixed to the crank (32) of the upper blade. By means of the sprocket wheels (55) and (56) with inter¬ mediate idling sprocket wheel (57), the crank (33) is fixed in its movement to the cr>ank (34) . 0 Therefore, by means of the pins (29) and (30) and the bush ings (23) and (24), the pair of cranks (33) and (34) deter¬ mine the movement of the lower blade (16) in synchrony with the second pair of cranks (37), (38) connected bythe connecting rod (42) and by other gears similar to those 5 already described for the first pair of cranks. The crank (32) is connected to the crank (31) by means of • ' the connecting rod (39) realized with the frame (17) and with the connecting rod (41) of the same frame, fixed to the bushings (21) and (22). 0 Therefore, the cranks (35) and (36) at the other end of -- the frame (17) for the blade (15) are also made to move by mechanisms substantially the same as those already des_ cribed for the lower blade,as the shafts for the two pairs of e ' ranks respectively, on either side of the upper blade, 5 are connected one to another by sprocket wheels like those already described (55), (56) and (57) and of which, for the sake of simplicity, only the sprocket wheel (59)fixed to the shaft of the crank (32) is indicated. Synchrony of movement of the paris of cranks (33-34) and 0 (37-38) for the lower blade, and (31-39, (35-36) for the upper blade is ensured by the two horizontal shafts (70) and (71) supported on bearings like (60), (61) placed on on the sides like (13) and (14) of the uprights (11) and (12). 35 Each of the two shafts is connected to the drive shaft(50) by means of gears like (62), fixed to the shaft (70) that engage with the sprocket wheel (53) mounted, as already explained, on said shaft (5.0). On the upright (12) the shaft of crank (37) supports ano- ther sprocket wheel, not shown in the drawing, that enga¬ ges a pinion fixed to the other end of the shaft (70) and carries out the same functions as the gear (62) . Mechanisms similar to those already described connect the shafts of cr^ks (31) and (35) with the longitudinal shaft (71) for synchronizing movement of the pairs of cranks for the upper blade. An elastic presser is fixed to the connecting rods (39), (41) of the upper blade. Figure 4 clearly ' shows the movements made by the upper(l5) and lower (16) blades in their various positions as these positions change ( 1 5 * ) , (15 ? )» 5,) - >■& respectivel (16 1 ) , (l6 ), (16,), due to movement of the cranks. At each shearing cycle the blades start from and return to the upper resting points (15- t ) and (16. * ). When they have reached positions (15,) and (16,),the blades travel together with the band, little by little increasing the amount of superimposition,as they approach their lower resting points (15) and (16), and thus generating the cut. The start of each shearing cycle to cut off the desired length of band, as well as regulation of blade rotation speed in each cycle according to the speed at which the band moves, is operated, automatically by an electric con¬ trol panel which memorizes the information received from sensors applied to. the band and which, according to the speed at which it moves, and to a program put in on a key¬ board or by some other controls, operates one or more cut¬ ting cycles for detaching one or more equal or different lengths of band, as required. The advantages offered by the invention are evident. To summarise, though the band is continually moving, clean and precise cuts can be obtained, in the desired lengths, with the blades remaining always parallel in their cutting' movements even though their trajectories are circular, and therefore being always transversal to the piece to be cut. Compared therefore with the shearing machines at present in use, cutting is done at a speed .and with a degree of precision never before achieved. As the applications of the invention have been described as examples only, not limited to these, it is understood that every equivalent application of the inventive con¬ cepts explained, and. any product manufactured and/or in operation according to the characteristics of the inven¬ tion will be covered by its field of protection.

Claims: ' Claims 1. Guillotine shearing machine, especially for cutting con tinuous metal bands, characterized in that each of the two longitudinal blades (15), (16) translates in synchrony one towards the other, parallel to each other, along equal cir cular trajectories, with rotating axes lying on the same geometrical plane, the two blades (15), (16), meeting at each cutting cycle consisting of a 360° rotation, made in proximity to the cutting plane, little " by little becoming superimposed for making the cut, blade speed being regula¬ ted during the cycle and the start of each cycle being con trolled, in relation to the speed of the band (90), in such a way that, in the zone of contact, the speed of blades(1 ), (16) coincides with that of the band (90) and the piece of band (90) is cut off at whatever length is 'desired. 2. Guillotine shearing machine, especially for cutting con tinuous metal bands as in claim 1 , characterized in that movement of the blades (15), (16) is procured by a double pair of cranks (31-32), (35^36) -and (33-34), (37-38) for each of the two blades (15), (16), each of said two pairs (31-32), (35-36) and (33-34), (37-38) being placed one at either end of the blades (15), (16), the two cranks(31-32), (35-36) and (33 J -34), (37-38) of each pair being connected together by sprocket wheels (55), (56) with an interposed idling sprocket wheel (57), both axes of rotation of the two pairs of cranks (31-32), (35-36) and (33-34), (37-38) for each of the blades (15), (16) being set on the same plane transversal to the cutting plane. 3. Guillotine shearing machine, especially for cutting con tinuous metal bands as in claim 2, characterized in that the pairs of cranks (31-32), (35-36) and (33-34), (37-38) for each of the blades (15), (16) are connected together by a longitudinal shaft (70), (71) to ensure their synchro_ nized movement, this preferably being done by means of pairs of gears. 4. Guillotine shearing machine , especially for cutting continuous metal bands, as in claims 2 and 3, character¬ ized in that the drive shaft (50) is fixed to one upper crank (33) of the lower blade (16) connected on the same side (14) of the machine (10) by means of a pair of sproc¬ ket wheels (53), (54), and to a lower crank (32) for the upper blade (1 ), the synchronizing shafts (70), (71) be¬ tween the pairs (31-32), (35-36) and (33-34), (37-38) of cranks respectively for each of the blades (15), (16) be- ing connected by gears (62) to sprocket wheel (53) fixed to the upper cranks (33), (37) of the lower blade (I6)and to the sprocket wheel (54) fixed to the lower cranks (32), (36) of the upper blade (15). 5. Guillotine shearing machine, especially for cutting continuous metal bands as in claim 2, characterized in that each of the two ends of each blade (15), (I6)is fixed to a connecting rod (39-41), (40-42) said rods (39-41), (40-42) being respectively connected to the cranks (31-32), • (35-36) and (33-34), (37-38) of each pair on one side and the other of each of the above mentioned blades (15),(16). 6. Guillotine shearing machine, especially for cutting continuous metal bands as in claim 5, characterized in that the frame (17), fixed to the connecting rods(39-41) which, connect the two cranks (31-32) and (35-36) of each pair acting on the two ends of the upper blade (15), sup¬ ports an elastic presser (80) acting over the whole width of the translating band (90) accompanying its movement but at the same time stabilizing its vertical position. 7. Guillotine shearing machine, especially for cutting continuous metal bands as in claim 1, characterized in that the start of each cutting cycle and regulation of the speed of rotation of the blades (15), (16) in relation to the speed of the band (90) to achieve equal speeds at the moment of contact between the blades (1 ), (16) and the band (90), are automatically controlled by an electronic - 9 - system which memorizes the information received from sen sors applied to the band (go) and which, in accordance with the speed of its. movement and with the program fed into the system through a keyboard or some other method-, causes one or more cutting cycles to be made for cutting off one or more pieces of band (90), either the same or different, in the desired lengths.

Inventors: COLOMBO GIORDANO, COLOMBO, GIORDANO
Applicants: SALICO SNC
Application year: 1986
Main classification: B23D25
IPC codes: B23D25