US 2823748 A
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Description (OCR text may contain errors)
Feb. 18, 1958A L. H. PETEREIT A 2,823,748
SHEAR Filed July 25. 1955 2 sheets-sheet 1 INVENTOR. Lothar H. Pe'tev'eit United States Patent O SHEAR Lothar H. Petereit, Worcester, Mass., assignor to Morgan Construction Company, Worcester, Mass., a corporation of Massachusetts Application July 25, 1955, Serial No. 523,967
3 Claims. (Cl. 164-60) This invention relates to a shear and more particularly to apparatus for cutting moving strands of metal.
Many attempts have been made in the past to design a so-called drum shear with retractable knives for cutting a moving strand of metal as it passes at undiminished speed. For various reasons, none of these attempts have been successful. In a knife of this type it would be cntemplated that Va retraction of the knives take place in order that exertmely long lengths could be cut without greatly diminishing the speed of the shear. However, the means for retracting the knives that have been evolved in the past in shears of this type have been complicated, unwieldy, and subject to continual maintenance problems, so that this type of shear has never come into general use. These and other diiculties experienced in the past with the prior art have been obviated by the present invention.
It is, therefore, an outstanding object of the present invention -to provide a shear of the type having retractable knives, which may be operated easily and accurately.
Another object of this invention is the provision of a drumtype shear whose knives are retractable by a simple and rugged mechanism.
It is a still further object -of the instant invention to provide a drum-type shear having hydraulically or pneumatically actuated retractable knives.
A further object `of the invention is to provide a rotary shear which will be comparatively simple and inexpensive to manufacture and thoroughly reliable inloperation.
With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.
The character of the invention, however, may be best understood by reference to certain yof its structural forms as illustrated by the accompanying drawings in which:
Figure l is a partially-sectioned, elevational view of the invention as it appears when looking in the direction of movement of the metal strip.
Figure 2 is an enlarged sectional view of a portion of the invention, and
Figure 3 is a sectional view of the invention taken on the line III-III of Figure 1.
.Referring first to Figure l, wherein is best shown the general features of the invention, the shear, indicated generally by the reference numeral 10, is shown as comprising a main housing 11 mounted on a suitable foundation. Situated at one side of the housing 11 is an upstanding support 12 which in the preferred embodiment is a boxlike weldment. Extending through the housing 11 is an upper shaft 13 and a lower shaft 14. The upper shaft 13 is supported Iat one side in a roller bearing 15 and at the other side in a roller bearing 16. A bull gear 17 is keyed to the shaft 13 at a central position intermediate of the bearings 15 and 16. In a similar way, the shaft 14 is provided with a roller bearing 18 at one side and a bearing 19 at the other side, while a bull gear 20 is keyed to an intermediate position of the shaft within the housing 11. The bull gears 2,823,748 Patented Feb. 18, 1958 ICC 17 and 20 mesh for inner driving relationship and are driven by means, not shown and not forming part of the present invention. It should be noted that the roller bearings 15 and 18 are of the type which provides for the absorption -of axial forces as well as radial forces, where as the roller bearings 16 and 19 in the preferred embodiment are designed only as radial bearings. The shaft 13 extends through the bearing 15 and outwardly of the housing 11, and on this outwardly-extending end is fastened a block 21, which rotates with the shaft and which carries a knife holder 22. In the same way, the 4lower shaft 44 is provided with a `block 23 in which is mounted a knife holder 24. The shaft 13 is provided with an internal bore 25, which extends entirely through the shaft. In this bore 25 is mounted in suitable bearings .a knife-actuating shaft 26. A spur gear 27 is keyed to the shaft 26 in the portion thereof which resides within the block 21 and `this spur gear meshes with a segmental gear 28 formed on the periphery of the knife holder 22. The block 21 is formed in two pieces, consisting of an internal portion 29 to which the shaft 13 is keyed and an external cover portion 30 which is suitably connected to the internal portion 29. As is evident in the drawing, the gear 27 is mounted on the shaft 26 and is restricted lengthwise between the outer end of the shaft 13 and the inner surface of the cover portion 30. In the same way, the knife holder 22 is held between the lcover portion 30 and the inner portion 29. The knife holder is pivotally-mounted on a shaft 31, which is keyed to and extends between the inner portion 29 and the cover portion 30 of the block 21 and a suitable bearing 32 is placed between the knife holder and the shaft 31.
At the other end of the shaft 13 and externally of the housing 11 is situated a vane-type, rotary, hydraulic mot-or 33. This motor 33 is of a well-known type having an external housing 34 and an internal rotor 35; this motor is so constructed that admission of oil or air pressure to one side of .the vane causes the rotor 35 to rotate rapidly `through a predetermined angle relative to the housing 34. In the instant case, the required angle of rotation of the rotor is small, being in the order of 60. The housing 34 of the motor 33 is directly .attached to the shaft 13 while the rot-or is coupled to the knife-actuating shaft 26. A suitable oil seal 36 and suitable friction seals stand between the housing 11 and the housing 34 of the motor 33. A similar motor 37 is associated with the shaft 14 and corresponding elements associated therewith. The housing 34 of the motor 33 is provided with ports 38 and 39 to which are attached flexible oil conduits 4I!) land 41, respectively, connecting the motor to a rotary hydraulic commutator 42 fastened to the support 12. Oil conduits 43 and 44 are provided in a similar manner, to connect the motor 37 to a rotary hydraulic commutator 45 which is 'also supported on the support 12. Conduits 46 andl 47 connect the commutator 42'to conduits 48 and 104, rcspectively, leading to a source of pressure oil, not shown, while a similar pair of conduits 49 and 50 perform a similar service for the commutator 45.
Referring now to Figure 2, the construction. of the rotary hydraulic commutator 42 may be easily seen. The commutator consists of an external housing 51 which is xedly-mounted on the support 12 and an internal rotary member 52 which rotates within that housing. The rotary member 52 is of generally solid circular cylindrical form which is mounted at one end in a ball bearing 53 and at the other end in a ball bearing 54, both bearings being iixedly-mounted in the housing 51. In addition, a sleeve 55 is mounted within the housing 51 and lies between the bearings 53 and 54 and between the internal surface of the housing 51 `and the external surface of the rotary member 52.` A set screw 56 is provided to prevent rotation of the sleeve 55. The oil conduits 40 and 41 are threadedly-fastened to therotary member .5,2 v4at ports 57 ,and 58.respectve1y. The ports 57 and 58 merge into axial action longitudinal passages 59 and 60 respectively. Passage 59 is considerably shorter than the passage `6 0 and .atsits end `isa radial passage 61 which mates with an yaperture 62 in 4the sleeve -55 and with a port 63 in the housing 51 yto which the oil conduit 46 is threadedly-connected. In a similar manner, the longitudinal passage 60 has a t-ransverse passages64 formed at right angles to lits inner end and leading to an aperture l65 in the sleeve 55 which, in turn, is aligned with a port 66 formed in the housing S1 and to which the oil conduit 47 is threadedly connected. A suitable oil seal 67 is provided at the area where the rotarymember 52 emerges from the housing 51. A number of bronze rings 68, 69, 70 and 71 are located in grooves formed on the outer cylindrical surface of the rotary member 52. The sizes of thegrooves and the `bronze rings being selected so that the bronze rings pair up in an oil-seal manner against the inner cylindrical surface of the sleeve 5,5. The ybronze rings 68 and 69 reside on opposite sides of a broad oil groove 72 formed in the exterior surface of the rotary member 52 onto which grooves 72 and passage .62 open. A similar oil groove 73 is formed on the exterior surface of the rotary member which has the passage 64 opening into it.; this oil lgroove 73 has the bronze rings 70 and 71 on either side of it. In addition, Va torsion rod 74 extends between the motor 33 and the commutator .42. The torsion rod consists of a rst section 75 which is `threaded into :the housing 34 of the motor 33 axially thereof and -between thelports 38 and 39, a second portion 76 Which is threaded into the rotary member 55 kof '.the .commutator .4,2 axially thereof between the ports 57 and 58, and a sleeve 77 which extends lbetween the first and second portions 75 and 76. The sleeve 77 transmits torque between the two portions and compensates for any .misalignrnenu The sleeve is held on the portions by clamping ring 78 and 79.
Referring next to Figure 3, which best shows the construction and arrangement lof the block 21 and its associated members, it can be seen that the inner portion 29 of the block 21 provides a pocket within which the spur gear 27 may reside. At one side of the spur gear, the inner portion of the block is cut out to provide a at surface 80 and to define a wing 8 1. A bore 82 eX- tends through this wing from the surface 80 to the lower part of the wing and the lsleeve 83 resides in this bore. A stop bolt 84 resides in the sleeve 83 and is threaded therein. A vsuitable locking nut 8S is threaded on the bolt `84 and contacts the surface 80 assuring that the stop bolt remains in its selected position. In a similar way, the inner portion 29 of the housing is cut away on the opposite side of the shaft 26 to provide a `flat surface 86. The surfaces 80 and 86 are generally radial with the axis of the shaft 26 as their center of radius. They extend atan angle of approximately 170 to one another. The surface 86 helps to dene a wing 87 from which extends a bore 88 in which resides a sleeve 89. A Aset bolt 90 is threaded through this sleeve and is provided with a lock nut 91 threaded thereon and contacting the surface 86. Figure 3 shows particularly well the manner in which the gear segment 28 is formed in a generally circular manner, is concentric with .the shaft 31 and subtends an angle of approximately 90. A knife holder 22 Ais provided with abutments 92 and 93 which are provided with hardened inserts 94 and 95 respectively. The inserts are so 'located that, when the knife holder is rotated in one direction, the insert 94 strikes the bolt 84, while when it is rotated in the other direction, the insert 95 strikes the bolt 90. The inserts 9.4 and 95 are provided with plane surfaces and these surfaces are generally tangential to the pitch circle of the gear segment 28. This means, of cou-rse, that the insert surfaces are at an angle of approximately 90 to one another. The knife holder V22 is also provided with an outwardly extending ilange 96 providing a plane surface 97. A reinforcing web 98 extends between the flange 96 and the abutment 93 in the side of the flange away from the surface 97. To the surface 97 is bolted the knife 99 by means of bolts 10i). Flat spacers 101 and 102 are provided between :the knife 99 and the knife holder 22 to obtain absolutely correct location of the knife. The construction of the knife holder 24 and the block 23 is similar in every yrespect to that just described above, ,and the knife holder 24 has fastened thereto a lower knife 103.
The operation of the apparatus of the invention will now be clearly understood in view of the above description. The .bull gears 17 k.and 210 are driven and they, in turn, cause the shafts .13 and 14 to rotate in their bearings. The rotation of the shafts 13 and 14 in turn rotates the blocks 21 and 23, respectively, carrying with them the knife holders 22 and 24. A strip of metal passing between the blocks 21 and 23 will be severed by the knives 99 and 103 yupon every revolution if the knife holders are in the position shown in Figure 3. in this position, the insert k94 is pressed against the set bolt S4 and the knife 99 is yincutting position. When the yknife holder is Vrotated so that theinsert 95 on the abutment 93 is pressed against the set bolt and the knife is drawn into an inward position closer to the center of the shaft 26, it is not in a position to mesh with the corresponding blade 103 on the knife holder 24. In order to move the knife holder from the operative to the inoperative position, the knife holder is rotated about thc center of the shaft 31 Athrough an angle vless than 90. This is done by rotating theshaft 26 and the spur gear 27 through an appropriate angle which will depend upon the relative diameters of gears 27 and gear segment 28. It will be understood, of course, that the shaft 26 is rotating with the shaft 13, so that the intermittent rotary motion just described is added to or subtracted from its continuing rotation with the shaft 13. Such additional or differential motion of the shaft 26 Vis accomplished by means of the hydraulic vane` type rotary motor 33, the motor 33 in its entirety being attached to the shafts 13 and rotating with it. If it is desired to bring about a differential motion in the shaft 26, it is only necessary to supply hydraulic power to the proper side of the vane on the rotor 35 of the motor 33. The rotor then turns almost instantaneously to a preselected angle relative to its lhousing 34. Thus it is that the shaft 26 is given the same differential motion and if vthis `motion is in addition to the rotary speed and in the same direction, of the speed of the shaft 13, the knife holder will be moved from a position wherein the insert 94 contacts the bolt 84 to a positionin which the yinsert contacts the Abolt 90, and the knife is in retracted posi` tion. If it is desired to go in the opposite direction and move the knife into operative position, it is only necessary to subtract from the normal speed of the shaft 26. Oil is introduced to the rotor of the motor 33 in such a manner that it moves in the reverse direction relative to Vits housing 34, causing the shaft 26, for a moment, to go slower than the shaft 13 and thus rotating the knife holder to bring the knife into operative position. The controls whereby the pressure oil is introduced to the proper side of lthe vane on the rotor 35 of the motor 33 are external of the apparatus and do not form a part of the `present invention. The conduits 48 and 104 are connected to the Source of pressure oil and to the control valving which serve to transmit the pressure oil in the pre-selected manner to the hydraulic motors 33 and 37. Since the conduits leading into the shear carrying pressure oil are fixed, it is'necessary to provide some sort of rotary apparatus for transmitting the oil under pressure, ,and this is provided by the hydraulic commutators 42 and 45. Referring to Figure 2, it will be understood that the ports 38 and 39 ofthe motor 33 lead to opposite sides of the vane on the rotor 35 thereof. It will be understood that oil under pressure will be introduced to one ofthe conduits 46 and 47 of the rotary valve 42 while the other one will be set to permit the oil to iiow outwardly thereof. The oil entering or leaving the conduit 47 will flow through the port 66 in the housing 51 through the aperture 65 in the sleeve 55, enter the oil groove 73 and the passage 64. It will pass along the passage 60 through the port 58, through the conduit 41 and the port 39 to one side of the vane on the rotor of the motor 33. While entering or leaving, the oil in the conduit 46 passes through the passage 63 in the housing 51, through the aperture 62 in the sleeve 55, the groove 72, the passage 61, the passage 59, the port 57, the conduit 4i), and the port 38 giving access to the other side of the vane of the rotor of the motor 33. The bronze rings 68, 69, 70 and 71 prevent unnecessary leakage of the pressure oil and the seal 67 further insures that there be no oil leakage. It will be understood that, as the motor 33 revolves with the shaft 13, its housing also revolves so that it will be necessary to carry the rotor 52 of the commutator 42 along with it. Since the oil conduits 40 and 41 are not designed to transmit torque forces and would fail if subjected to such forces, the shaft 74 is provided and it serves to transmit the torque between the housing 34 of the motor 33 and the rotor 52 of the commutator 42. Rotor 52 thus revolves continuously and serves to carry any oil signals which arrive at the conduits 46 and 47 to the motor 33 for the operation thereof.
It can be seen that there are a number of desirable features which are obtained by the use of the present invention. It is possible, of course, to adjust the extreme positions of the knife holders by adjusting, in the case of the knife holder 22, the bolts 84 and 90. Usually, for instance, the angle within which the rotor of the hydraulic motor 33 will be moved would be selected to be slightly greater than the angle within which the knife holder is desired to be rotated. This means that the insert 94 will strike the bolt 84, for instance, some time before the rotor within the motor 33 has reached its extreme position, the rotor will be maintained with pressure on that side of the vane and this will hold the knife holder 22 in firm solid Contact with the stop bolt 84 during the cutting operation. This, of course, would only be possible when a hydraulic device is used, since a mechanical movement of this type would necessarily be forced to move to its extreme position unless a spring buffer or the like were introduced into the mechanism. Furthermore, the movement of the knife blade from operative to inoperative position and vice versa may be controlled remotely. This is, of course, important in the operation of a rolling mill and it takes place almost instantaneously. It will be understood, of course, that the operation of the valving which controls the position of the knife may be made automatic; this would be desirable for instance, if it were wished to cut long lengths of metal by having the knife in operative position at one revolution of the block 21 and in inoperative position at the next revolution and so on continuously. The automatic rotary valving would take care of this automatically. Thus the device lends itself equally well to manual or automatic control.
It is obvious that minor changes may be made in the form and construction of the invention without departing from the material spirit thereof. It is not, however, desired to confine the invention to the exact form herein shown and described, but it is desired to include all such as properly come within the scope claimed.
The invention having been thus described what is claimed is new and desired to secure by Letters Patent is:
l. A shear comprising a housing, a first shaft rotatablymounted in the said housing, a knife holder mounted for rotation with the first shaft and hindredly-mounted for additional positional movement from a first position to a second position, a second shaft mounted for rotation with the first shaft, means connecting the second shaft to the knife holder to bring about the said movement from the first position to the second position, a rotary motor having a housing connected to the first shaft for rotation therewith and a rotor connected to the second shaft, the actuation of the motor causing a differential rotation in the second shaft relative to the first shaft to cause the said positional movement of the knife holder, and means rotatable with the motor housing to permit the introduction of an actuating signal to the motor during its rotation with the first shaft.
2. A shear comprising a housing, a first shaft rotatablymounted in the said housing, a knife holder mounted for rotation with the first shaft and hindredly-mounted for additional positional movement from a first position to a second position, a second shaft mounted for rotation with the first shaft, means connecting the second shaft to the knife holder to bring about the said movement from the first position to the second position, a rotary hydraulic motor having a housing connected to the first shaft for rotation therewith and a rotor connected to the second shaft, the actuation of the motor causing a differential rotation in the second shaft relative to the first shaft to cause the said positional movement of the knife holder, and means rotatable with the motor housing to permit the introduction of an actuating fiuid to the motor during its rotation with the first shaft.
3. A shear as recited in claim 2 which said means includes a distributor rotatable with the motor housing to permit the introduction of an actuating fluid to the motor during its rotation with the rst shaft, saidl distributor including a fixed housing and a rotor having passages therethrough, conduits connecting the motor to the passages of the distributor rotor, conduits connected to the distributor housing for introducing the actuating iiuid thereto, and means connecting the motor housing to the distributor rotor so that they rotate together.
References Cited in the file of this patent UNITED STATES PATENTS 1,603,859 Midgley Oct. 19, 1926 1,625,862 Martin Apr. 26, 1927 2,587,732 Jaeger Mar. 4, 1952 2,612,656 Lyon Oct. 7, 1952 FOREIGN PATENTS 465,160 Germany Sept. 7, 1928