US3469477A - Board perforator and cutter - Google Patents

Description

Sept. 30, 1969 a. o. WELCH ETAL 3,469,477

BOARD PERFORATOR AND CUTTER Filed May 10, 1967 2 Sheets-Sheet 1 Fig.l

INVENTORS George D. Welch Leonard L. Donuhe AT TORN EY Sept. 30, 1969 a. D. WELCH ET AL 3,469,477

BOARD PERFORATOR AND CUTTER 2 Sheets-Sheet 2 Filed May 10, 1967 Fig. 2

INVENTORS George D. Welch BY Leonard L. Donohe ATTORNEY United States Patent Office Patented Sept. 30, 1969 US. Cl. 838 1 Claim ABSTRACT OF THE DISCLOSURE Relative to a board perforator and cutter, as disclosed in US. Patent 2,345,072, there is disclosed herein an improvement wherein the lowering and raising of the axis of the upper rotary knife blade, for respectively cutting a board or perforating a board passing between it and a lower knife blade, is accomplished by the sequence of advancing or retracting an air cylinder piston and an attached spur gear each, which rotates, approximately 180 one way or the other, a spur gear, rotating a cam, and causing lowering or raising of the two slidable, spring loaded slide plates in which the upper knife rotor is journalled.

Background of the invention Prior cutting and perforating machines, primarily for use on plaster board or the like, such as that disclosed in US. Patent 2,345,072, also included a cam, the rotation of which lowered and raised two slidable spring loaded slide plates in which the upper knife rotor was journalled. Rotation of the prior cam, however, con sisted of one uniform speed continuous single revolution of the cam, driven by engagement of a positive drive jaw clutch which was driven by the same drive means that drove the two rotary knives. Although not shown in the prior patent, a drag brake was also required to stop the rotation of the cam immediately on disengagement of the associated jaw clutch, which, if the jaw clutch started to open somewhat early, resulted in uneven perforations, cutoffs and board lengths. With the prior complete revolution of a cam providing the upper and lower positions of the upper knife rotor, adjustment of these positions required replacement of the cam.

Summary of the invention The present invention relates to the combination, with a machine for alternatively cutting or perforating board, of improved means for lowering and raising the upper knife rotor, to thus change to cutting and to perforating positions, respectively. Briefly, the improved means comprise an independent drive means for rapidly rotating the cam which causes the vertical movement of the upper knife rotor, preferably rotating the cam less than 180 and reversing an equal amount, to provide easily controlled amounts of lowering and raising.

Drawings FIG. 1 is an end view of a board perforator and cutter, embodying the present invention.

FIG. 2 is a right-side view of the drive portion of the machine of FIG. 1, which is the portion adjacent the end shown in FIG. 1. a

Preferred embodiment Referring to the drawings, it will be seen that there is illustrated a machine very similar in many respects to the machine disclosed in Patent 2,345,072, issued Mar. 28, 1944. In the present disclosure, the means for driving the rotor shifting cam is different, and are identified in the drawings by numerals starting with the numeral 200. Lower numerals will be seen to correspond with the identifying numerals used in US. Patent 2,345,072, relative to elements of the present invention which are similar to the elements of the said patent.

In the drawings there will be seen the machine bed 10 mounted on feet 11 and supporting two end frames, only the left end frame 13 being shown in FIG. 2, in which end frames the two ends of lower rotor 16 are solidly journalled, only left end 15 being shown. The rotor 16 carries four knives 17, 18, 19 and 20, spaced apart on its periphery.

A suitable solid continuous drive is provided for lower rotor 16 at the remote end thereof not shown in the drawings.

A continuation 31 of the end 15 of the rotor 16 is journalled in a supplemental end frame 32 mounted on the bed 10, and carries a gear 33 continuously meshing with a gear 34 of equal pitch diameter mounted on a stub shaft 35 journalled in the frame member 32. To one face of the gear 34 is secured one member 36 of an Oldham coupling of well understood construction, while the mating element 37 of said coupling has secured toaits outer face a jaw clutch element 38. The elements 37 and 38 are axially loosely mounted on a shaft 40 extending from one end of an upper rotor 41. The shaft 40 is journalled in suitable bearings in a bearing carriage, or slide plate 43, vertically slida-bly mounted respectively in the end frame 13, as is also a shaft at the other end of upper rotor 41. The slide plate 43 is guided for vertical movement in a guideway 44 formed in the end frame 13. The guide plate is constantly supported and urged upwardly by a spring 45. With the other end of the rotor 41 similarly mounted, it will be seen to be transaxially shiftable toward and away from rotor 16.

Integral with plate 43 is a platform 46 formed to hingedly mount a pintle 48 to which are fixed a pair of yoke arms 49 provided with shoes 50 diametrically oppositely received in an annular groove 51 formed in a clutch element 52 fixed on shaft 40 adapted to mate with clutch element 38. At least one of said arms is provided with an extension 53 with which is associated a coiled spring 54 urging said yoke arms to swing in a counter-clockwise direction; as viewed in FIG. 2, to move said clutch element 52 into cooperative relation with the element 38; but said element 52 is normally restrained against such movement and held in the position illustrated in FIG. 2 by the engagement of a trip dog 55 with the thickened portion 56 of an annular cam collar 57 integral with or fixed to said element 52.

As is clearly shown in FIG. 2, the dog 55 is reciprocably mounted in a lug 58 carried on said platform 46, and is held in position by a finger 59 on a rockshaft 60 journalled in bearings 61, 61 depending from the platform 46, and carrying a lever 62 with which is associated a coiled spring 63 tending to rotate said lever in a clockwise direction as viewed in FIG. 2 and thereby holding the dog 55 in its illustrated position.

It will be obvious that the driving train thus far described will produce continuous rotation of the rotor 16, and will effect rotation of the rotor 41 only when the clutch element 52 is engaged with the clutch element 38; and that the provision of the Oldham coupling permits the transmission of movement from the stub shaft 35 to the rotor 41 whether or not those members are in axial alignment. A single knife '64 is carried by the rotor 41.

In the illustrated positions of the parts, the dog 55 cooperates with the thickened portion 56 of the cam collar 57 to hold the clutch element 52 out of engagement with the element 38. counterclockwise movement of the lever 62, however, in opposition to the spring 63, Wlll withdraw the dog 55 to permit the spring 54 to move the element 52 into cooperative relation with the constantly rotating element 38 to drive the element 52 and the rotor 41. If the lever 62 is now promptly released, the spring 63 will urge the dog 55 into engagement with the peripheral surface of the collar 57 of the rotating element 52; and as said element rotates, the thin portion of the collar will come into registry with the dog 55 to permit said dog to move upwardly into contact with the left-hand, cammed face of said collar. Thus, as the rotor 41 approaches completion of a revolution, the dog 55, acting on the cammed face 56 of the collar 57, will shift the element 52 to the right to disengage said element from the element 38. Preferably, a spring-pressed brake not shown is associated with a projecting portion of the end not shown of the rotor 41 to stop said rotor promptly upon disengagement of said clutch elements, the brake 65 being mounted to partake of the transaxial movement of the rotor 41.

Beyond the supplemental end frame 32, the extension 31 carries a bevelled gear 66 meshing with a gear 67 fixed on a shaft 68 journalled in suitable brackets 69 and 70. The shaft 68 carries a sprocket 71 connected, by a chain 72 to drive a double sprocket 73, 74 suitably journalled on the machine frame. The chain 72 engages the portion 73 of the last-named sprocket; and a control chain 75 hangs loosely on the sprocket portion 74, said chain 75 carrying one or more suitably positioned trip elements 76. It will be clear from the above that the chain 75 is driven with the continuously rotating rotor 16, and, at predetermined points in the cycle of the rotor 16, a trip element 76 will be caused to engage the lever 62 to swing the same in a counterclockwise direction to withdraw the dog 55 to permit engagement of the clutch element 52 with the element 38, and that thereupon the rotor 41 will be turned through one revolution, upon the completion of which the now-released dog 55 will cause disengagement of the element 52 from the element 38, and the said spring pressed brake will stop the rotor 41.

Of course, the chain 75 will be so associated with the sprocket 74 as to trip the clutch mechanism at a time such as to bring the knife 64 into vertically downwardly directed position at a time to cooperate with one of the knives on the rotor 16. It will be obvious that the chain 75 can be so designed and proportioned as to cause the knife 64 to cooperate with any one of the knives on the rotor 16 upon each revolution of the rotor 16, or to cooperate with successive knives on the rotor 16. Thus, depending upon the selection of a chain 75 of suitable length or with suitably spaced trip elements 76, the rotor 41 can be caused to make one revolution for each revolution of the rotor 16, or one revolution for each one and one-fourth revolutions of the rotor 16, or one revolution for each one and one-half revolution of the rotor 16, or one revolution for each one and three-fourths revolutions of the rotor 16, or one revolution for any other number of revolutions of the rotor 16 in the same arithmetical progression. Thereby, the machine can be caused to cut material traveling therethrough to any desired length greater than the periphery of the orbit of the knives on the rotor 16 by any desired multiple of onefourth that length.

It is often desirable, particularly in working upon plaster board, to cause a cut-off machine to perforate the board at stated intervals between severing operations. It is for that reason that the rotor 41 is mounted for transaxial movement relative to the rotor 16, and we have provided means for automatically shifting the rotor 41 between that position in which the knife 64 will cooperate with one of the knives on the rotor 16 to sever the board and that position in which the knife 64 will cooperate with one of the knives on the rotor 16 merely to perforate the board without severing it. Referring, again, to FIGS. 1 and 2, it Will be seen that the slide plate 43 mounts a roller 77 adjacent its upper end, and that a cam 78 engages said roller to hold the slide plate 43 down against the tendency of the spring 45. It will be obvious of course that the other end of the rotor 41 is journalled in a similar slide plate provided with a similar roller with which cooperates a similar cam which is carried on the same cam shaft 79 with the cam 78.

Alternative means may be provided by which rotation of shaft 79 will effect vertical movement of slide plate 43 and rotor 41, such as, for example although not shown, forming shaft 79 to include an eccentric portion, in place of the cam 78, which eccentric portion is journalled in an extended portion of slide plate 43.

On an extension 200 of cam shaft 79 there is mounted a spur gear 202. Dispersed above and engaged with spur gear 202 is a horizontally disposed spur gear rack 204. At each side of spur gear 202, shaft extension 200 is journalled in bearing supports 206, 206, and atop each bearing support 206 is a small pillow block 208. A rack hold down wheel 210, with 'a small shaft 212 is rotatably mounted in the pillow blocks 208, 208, with the wheel 210 atop the spur gear rack 204 to hold the rack firmly engaged with spur gear 202 as the rack is caused to move longitudinally to rotate spur gear 202.

An air cylinder 214 is fixedly mounted on a side platform 216 extending outwardly from frame 32. Air cylinder 214 includes an axially reciprocatory piston rod 218 aligned with and aflixed to spur gear rack 204. Two high pressure air supply hoses 220 and 222 are connected one to each end of air cylinder 214 for causing reciprocatory movement of piston rod 218 and spur gear rack 204. Pressure in hose 220 moves the spur gear rack 204, to an extended position relative to the air cylinder, and subsequent pressure in hose 222 returns the spur gear rack to a normal retracted position. An adjustable stop 224 permits adjustment of the extent of the retraction of the spur gear rack 204.

High pressure air is supplied to either hose 220 or hose 222 in accordance with the position of an electrically operated four way air control valve 226. A controlled source of high pressure air is supplied to valve 226 through supply pipe 228 having therein an air regulator 230.

Actuation of valve 226 is accomplished in a timed frequency to provide for the cutting of board 232 at preselected lengths, it being understood from decriptive matter further above that intermediate of said cutting of said board the knife 64 may be made to cooperate with one of the knives on rotor 16 merely to perforate the board without severing it. Adjacent to the sprocket 71, and on the same shaft 68, is sprocket 234, rotating simultaneously with sprocket 71. Mounted above sprocket 234 is a sprocket 236, to which is fixedly mounted a series of sprockets 238, 238, 238 sprocket 236 is driven from sprocket 234 by chain 240, thus driving sprockets 238, 238', 238". Each sprocket 238 has suspended therefrom a chain 242, 242, 242", each of different pre-selected length and each carrying one or more suitably positioned trip elements 244. An electrical limit switch 246 is mounted above sprockets 238, and includes a lever 248 which is adjustable for actuation selectively by the trip element 244 of any one of the chains 242, 242 or 242". A coiled spring 250 maintains lever 248 in a normal vertical position until moved by trip element 244. Limit switch 246 is connected to valve 226 by wires 252, 252.

When lever 248 is moved counter-clockwise, FIG, 2, by trip element 244, switch 246 activates valve 226, allowing high pressure air to flow into air cylinder 214 through hose 220, and allowing air in hose 222 to escape to atmosphere. Piston rod 218 and spur gear rack 204 move left, FIG. 1, to an extended position, rotating spur gear 202 and cam 78 counter-clockwise, slightly less than half a revolution. Cam 78, by its shape, thus moves roller 77 and its associated slide plate 43 downward, also moving rotor 41 and knife 64 downward. It will be understood that this downward movement will be timed to occur as knife 64 is being rotated to cooperate with one of the knives on rotor 16. In the downward position the knife 64 cause the board to be severed, rather than merely perforated, as occurs when rotated in its upward position.

Upon release of lever 248, it is returned to a normal vertical position by spring 250. Switch 246 activates valve 226 to return spur gear rack 204 to its normal retracted position, rotating the spur gear 202 and cam 78, clockwise, to normal positions. Adjustment of this normal position, to adjust for various thicknesses of boards to be perforated, can be accomplished readily by adjustment of adjustable stop 224, on air cylinder 21 4.

It will be obvious that the minimum length of board which can be perforated or cut with the present machine is determined by the periphery of the orbit of the cutting edge of the knife 64. In practice this length is usually 48 inches. Since the rotor 16 is provided with four knives, equally spaced, it will be obvious that the machine is capable of cutting lengths greater than 48 inches by any desired multiple of 12 inches.

Having completed a detailed disclosure of the preferred embodiment of our invention, so that others may practice the same, we contemplate that variations may be made without departing from the essence of the invention.

We claim:

1. A cut-off machine comprising a pair of knife-carrying rotors mounted to cooperatively selectively perforate or sever a horizontally moving length of board material therebetween, means for driving said rotors, and means for transaxially moving one of said rotors relative to the other fixed axis rotor for respectively perforating or severing said board material, said means for moving said one rotor transaxially comprising vertically slidably mounted end plates in which said one rotor is journalled and a separately driven cam mounted relative to said end plates whereby rotation of said cam transaxially moves said end plates and said one rotor journalled therein, means for rotating said cam less than one complete revolution, in one direction for raising and the opposite direction for lowering said end plates and said rotor journalled therein, said means for rotating said cam comprising a shaft on which said cam is mounted and a spur gear mounted on said shaft for rotating said shaft and said cam, a spur gear rack engaging said spur gear, a high pressure air powered cylinder having a piston therein aflixed to said spur gear rack for selectively timed reciprocatory movement of said spur gear rack, and electrically actuated four-way air control valve having means for supplying high pressure air to either of the two respective ends of said high pressure air powered cylinder for moving said piston and spur gear rack in one or the other of the directions of their extent, and selective control means for electrically actuating said four-way valve comprising a plurality of coaxial spindles rotatably driven by said means for driving said rotors having chains thereon with selectively positioned trip elements on each said chain, a lever adjustably mounted for actuation thereof selectively by any one of said chain and trip element combinations, and an electric switch operated by said lever, said electric switch being connected to said electrically activated valve with means to provide activation of said valve upon mechanical activation of said switch.

References Cited UNITED STATES PATENTS 46,448 2/1-865 Clarke 83-8 X 2,169,575 8/1939 Youngfelt et al. 83-344 X 2,272,702 2/ 1942 Haegele 83-8 2,345,072 3/1944 Rosenleaf et al. 83344 X 3,202,029 8/1965 Morath 83528 X 3,296,909 1/ 1967 Hudak et al 83-305 FRANK T. YOST, Primary Examiner U.S. Cl. X.R.

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