US807730A

US807730A - Paper-cutting machine.

Info

Publication number: US807730A
Authority: US
Inventors: Talbot C Dexter
Original assignee: Individual
Current assignee: Individual
Priority date: 1905-02-17
Filing date: 1905-02-17
Publication date: 1905-12-19
Anticipated expiration: 1922-12-19

Description

N0. 807,730. PATENTED DEC. 19 1905. T. G. DEXTER.

PAPER CUTTING MACHINE.

APPLICATION FILED FEB 17. 1905.

8 SHEETS-SHEET 1.

@vwewwo c PATENTED DEC. 19, 1905. T. G. DEXTER.

PAPER CUTTING MACHINE.

APPLICATION FILED FBB.17, 1905.

8 $HEETS-SHBET Zv witnesses I ammo/Moe No. 807,730. YPATBNTED DEC. 19, 1905. T. 0. DEXTER.

PAPER CUTTING MACHINE.

AIPLIOATION FILED FEB.17, 1905..

y a SHEETS-SHEET s.

No. 807,730. PATENTED DEC. 19, 1905. T. G. DEXTER.

PAPER CUTTING MACHINE.

APPLICATION FILED FEB.17, 1905.

8 SHEETS-SHEET 4.

wmeowo a w No. 807,730. PATENTED DEC. 19, 1905.

T. G. DEXTER.

"PAPER CUTTING MACHINE.-

APPLIGATION FILED PEB.17. 1905 3 SHEETS-SHEET 5.

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Wit mace mvawto c No. 807,730. PATENTED DEC. 19, 1905. T. 0. DEXTER.

PAPER GUTTING MACHINB. APPLIOATION FILED ran. 17, 1905.

8 SHEETS-SHEET 6,

No. 807,730. I PATENTED DEC. 19, 1905. T. 0. DEXTER.

PAPER CUTTING MACHINE.

APPLICATION FILED FEB.17, 1905.

8 SHEETS-SHEET 7.

No. 807,730. PATENTED DEC. 19, 1905. T. 0. DEXTER. PAPER CUTTING MACHINE.

APPLICATION TILED PEB.17, 1905.

8 SHEETSSHEET 8.

" NITED STATES PATENT ormo.

PAPER-CUTTING MACHINE.

Specification of Letters Patent.

Patented Dec. 19, 1905.

Application filed February 17, 1905. Serial No. 246,139.

To all whom it may concern.-

Be it known that I, TALBOT C. DEXTER, a citizen of the United States, residing at Pearl River, in the county of Rockland and State of New York, have invented certain new and useful Improvements in Paper-CuttingMachines, of which the following is a specification.

This invention relates to improvements in power-operated paper-cutting machines in which the sheets to be out are held firmly in proper position upon a supporting-table by means of a power-operated clamping-bar and are acted upon by a vertically-reciprocating laterally-movable cutting-blade which is automatically returned to its initial position and thrown out of operation at the completion of each cutting stroke, the power operated clamping device being adapted to maintain a predetermined amount of pressure upon the pile of sheets during the cutting operation.

The object of my present invention is to produce an effective and simple construction of paper-cutting machines which may be supplied to the trade at a relatively smaller cost than paper-cutting machines which are now on the market.

In my improved machine the knife is operated as usual. A pile-holding clamp is moved into engagement with the pile by means of rack-bars and gears operated from the powershaftthroughahand-controlled automaticallyreleased clutch and an adjustable frictional clutch which is adapted to force the clamp against the paper with a predetermined pressure and then slip, during the completion of the operative stroke for retaining the clamp, upon the pile during the completion of the cutting stroke. In addition to the mechanism for lowering the clamp by power I provide an independent mechanism by which the operator can. lower the clamp by foot-power, means being provided for disengaging the clamp from the power mechanism to allow it to be lowered by operation of a suitable treadle, the disengaging device being actuated by the initial movement of the treadle.

My present invention also includes improvements in the clamp-operating means for automatically throwing out the clamp-actuating clutch and for applying the brake and a device for manually disengaging the automatic throw-out from its actuating-cam in case the machine is stopped with these parts in engagement.

All of the said improvements will be hereinafter described with particular reference to the accompanying drawings and the novelty afterward more particularly pointed out in the annexed claims.

In said drawings, Figure 1 is a front elevation of a complete paper-cutting machine embodying my invention. Fig. 2 is a side elevation of the same. Fig. 3 is an enlarged detail rear view of the two sides of the ma chine, showing the operating-gears at the left and the frictional slip-clutch at the right, the interior and top portions of the machine being omitted. Fig. 4 is an enlarged detail side elevation of the frictional slip-clutch, showing also other parts of the machine at that side. Fig. 5 is an enlarged detail vertical sectional view showing the main clutch of the machine, the brake, and the hand control of the clutch and brake. Fig. 6 is a detail front elevation of the same mechanism. Fig. 7 is a detail elevation of the mechanism for detachably connecting the clamp with its power-driven mechanism. Fig. 8 is a rear view of part of the same mechanism. Fig. 9 is another detail elevation of the latch which connects the clamp with its power-driven mechanism, this view showing the latch upon the opposite side to that shown in Fig. 7. Fig. 10 is a detail elevation of the foot-power mechanism for lowering the clamp independently of the power mechanism. Fig. 11 is a detail sec tional top view of the hand-wheel which operates the back gage, showing part of the lock for securing said hand-wheel. Fig. 12 is a detail side elevation of the same, and Fig. 13 is a detail of part of the lock.

The operating parts of the herein-described paper-cutting machine are supported in a suitable framework of any desirable construction best adapted for such purpose. A heavily-built framework is shown comprising the side frames or standards 1, firmly braced and connected by the top rail 2, the center rail 3, the bottom rock-shaft or rod 4:, and the transverse shafts hereinafter referred to. The reciprocating cross-head 7, carrying the cutterblade 8, is mounted to slide vertically and transversely ofthe machine in the guide-slots 9, formed in the side frames or standards 1. The cross-head 7 is anchored to the top rail 2 by means of an ordinary link 10, which is pivotally connected at its opposite ends 11 and 12 to the knife-supporting cross-head and the top rails, so as to cause the cross-head and knife-blade carried thereby to move laterally of the machine as it reciprocates vertically to impart to the knife a shearing cut.

Suitably journaled in the side frames or standards 1 in the bearings is the knifeoperating shaft 16, carrying at its outer ends the cranks 17 which are connected, through the links 18, with the opposite endsof the knife-supporting cross-head 7 When the knife-operating shaft 16 is rotated, the jointed links 18 will cause the cross-head and cutter-blade to reciprocate vertically and transversely of the machine in the slotted guides formed in the side frames or standards 1 in a manner well understood in the art.

The shaft 16, which operates the knife, is driven by means of a large gear 20, rigidly secured to one end of the shaft 16 (and carrying one of the cranks 17 and meshing with a driving-pinion 21, which is loosely journaled upon the power or driving shaft 22. main driving or power shaft 22 is suitably journaled in the side frames or standards of the machine, as shown at 23, said shaft carrying upon one end thereof the driving-pulley 24. Thisshaftisdriven byanysuitablepower through the medium of a belt operating the pulley 24. The driving-pinion 21 is formed integral with or rigidly'secured to an elongated hub or sleeve 30, said hub having also mounted thereon at its opposite or inner end a clutch rim or Wheel 31. The elongated hub '3O is journaled within one of the bearings 23,

while the power or driving shaft 22 is journaled Within said hub 30. (See Fig. The clutch-wheel 31 and the pinion 21, forming part of or secured to the elongated hub 30, are loosely mounted upon the power-shaft 22. The clutch-wheel 31 forms one part of an ordinary expansion-rim clutch, the other part being a split clutch-ring 32, which is rigidly secured to the power-shaft 22. J ournaled at one end of the split-ring 32 is an operatingfinger 34, formed with a heel 35, adapted to engage the other end of the split ring, so that when the finger 34 is moving outwardly the split ring will be expanded to frictionally engage the interior surface of the clutch rim or wheel 31. Carried on the free end of the finger 34 is an adjustable screw-bolt 36, which is adapted to be engaged by an operating-spool 37, mounted to slide longitudinally upon the power-shaft 22 and formed with an annular groove 38, in which engage the inwardly-projecting pins 39, carried by the yoke 40, secured on the end of the operating-rod 41, as shown in Fig. 5.

From the construction above described it will be observed that when the rod 41 is oscillated to move the operating-spool 37 into engagement with the clutch 31 the clutch rim or wheel 31 will be frictionally connected with the power-shaft 22 and will drive the pinion 21, which operates the gear 20, said gear in turn rotating the shaft 16, thereby operating the cutter-blade. The rod or shaft 41 is suit- The ably journaled in the depending brackets 42,

rigidly mounted upon the central rail3 of the machine-frame. At the forward end of the rod or shaft 41 is mounted a hori'Zontally-projecting rock-arm 43, connected, through link 44, with the rearwardly-projecting rock-arm 45, keyed to a short rock-shaft 46, journaled in a bracket 47, secured to the front portion of one of the side standards 1. This short rock-arm 46 carries an upwardly-extending hand-lever 48, by the operation of which the rod or shaft 41 may be oscillated for throwing the clutch 31 32 into and out of operation.

50 is a band-brake partially encircling the outer clutch .wheel or rim 31 and having one end riveted to adjusting-bolt 51, which passes freely through a bracket-plate 52, secured to the framework of the machine, and is held in desired adjusted position by means of nuts 53 54, engaging the threaded end of the bolt 51. The other end of the brake-band 50 is riveted at 55 to a short lever 56, which is journaled at 57 upon the bracket-plate 52. Pivoted to the end of lever 56 at its end 58 is an upwardly-extending rod 59, which projects up through an eyebolt 60, secured to the framestandard 1 by means of nut 61. This rod 59 supports an expansion-spring 62, which engages the eyebolt 60 at its upper end and is adjustably confined at its lower end by means of an adjusting-nut 63, which is threaded upon the rod 59. The action of the spring 62, operating through rod 59 and lever 56, is to apply the brake to the clutch rim or wheel 31. The lever 56 extends to the left of bracket 52, as shown in Figs. 1 and 6, and carries in its bifurcated free end an antifriction-roller 65, which rests beneath a cam-shoe 66, formed upon the lower end of a rock-arm 67, which is keyed to the rock-shaft or rod 41. It will be observed that with this construction of braking device the arrangement is such that the brake-band is active when the clutch is thrown out, so as to stop the machine instantly. When, therefore, the rock-shaft or rod 41 is moved to throw in the clutch, the

brake-shoe 66 will be moved inwardly to act upon antifriction-roller 65, so as to depress said roller and raise the opposite end of lever 56, and thereby release the brake-band. When the clutch is thrown out by the opposite movement of rock-shaft 41, the antifriction-roller will be freed by the reverse movement of the. cam-shoe 66 to allow the spring 62 to apply the brake. In the operation of paper-cutting machines it is desirable to have the operation started at the will of the operator; but the operation must be arrested automatically by the action of the machine. To accomplish this, I have provided another rock-arm 70 upon the rockshaft 41, to the lower end of which is freely pivoted a horizontally-presented thrust-bar 71, which extends through a suitable opening (not shown) in one of the side standards 1 and carries in its outer bifurcated end a freely-journaled antifriction-roller 72. This antifriction-roller 72 is presented in the path of a kicker-cam 73, secured to the cutter-operating gear 20, so that once in each revolution of the gear 20 cam 73 will engage the antifriction roller 72 and force rod 71 inwardly to rock the rod or shaft 11 and automatically throw out clutch 31 32 and apply the brake.

It sometimes happens in the operation of this machine that the machine will be stopped with the kicker-cam 73 in engagement with the antifriction-roller 72. This happens usually when the machine is stopped for some emergency by the action of the hand-lever 48. In such a case it would ordinarily be impossible to start the machine again for the reason that the cam 73 would prevent the outward movement of thrust-bar 71, which would prevent the rocking of shaft or rod 41, so that the clutch could not be thrown in. To avoid this contingency, the thrust-bar 71 is freely journaled to the lower end of a rock-shaft 70, as above explained, and is supported in an opening in the standard 1 sufficiently large to allow the outer end of the thrust-bar 71 to be raised out of engagement with cam 73. For the convenient raising of the bar 71 I provide a small footlever 75, journaled, on outside of the righthand side frame 1, upon a bolt 76, said lever having an upwardly and rearwardly extending angular portion resting directly beneath a vertical movable slide-rod 77, supported in suitable brackets 78, with its upper end directly beneath the thrust-bar 71. In case the machine is stopped with the cam 73 in contact with antifriction-roller 72 it will only be necessary to depress the foot-lever 75 and then operate the hand-lever 18 and again start the machine.

The paper-supporting platform or table is rigidly mounted between the side frames or standards 1 in the usual manner. Suitably mounted upon said table or platform is the adjustable back gage 81, the adjustment of which is controlled by means of a hand-wheel 82, journaled under the forward end of the table, said hand-wheel having a spirally-grooved drum portion 83, which carries thereon a band or cable 8 1, said band or cable in turn passing around the pulleys and 86, journaled beneath the table and connecting with the gageblock through lugs 87. Journaled in the top rail 2 is a flanged wheel 88, and journaled in the upper end of a suitable standard 89, projecting up from the rear end of table 80, is a similar wheel 90. These wheels are adapted to carry thereon an endless band or gage-tape 91. Projecting upwardly from the adjustable back gage 81 is an arm 92, which is also attached to the band or gage-tape 91, so that when said back gage is moved it will simultaneously move the band or tape-gage so that the operator standing at the front of the machine can be made aware of the exact distance of the back gage from the path of the cutter by observing the index-finger 93, secured to the top rail 2 and projecting downin front of the tape. Of course it is understood that this tape is scaled to meet the requirements of a paper-cutting machine of the style herein set forth. By the operation of handwheel 82 the back gage 81 can be moved toward or away from the plane of the cutter, the gage-tape moving simultaneously to indicate the position of the gages.

To securely hold the back gage in the desired adjusted position, I provide aclamp for locking the hand-wheel 82 against movement. This clamp is shown in Figs. 1, 11, 12, and 13 of the drawings and consists of a bracketplate 95, secured to the front face of the center rail 3 just under the table 80. Integral with the bracket-plate is a horizontal clamping-plate 96, which constitutes the stationary clamp member. A bolt 97 passes through a suitable opening formed in plate 96. 98 is the movable clamping-plate member also formed with an opening for the passage of bolt 97 and with a central cut-out portion 98, which fits over the contracted lower end of the bracket-plate 95 for preventing lateral movement of the movable plate 98. This plate 98 has formed upon its under face a cam lug or projection 98, which rests in engagement with the upper cam-face 99, formed on the hub of the operating-handle 99, which is also mounted upon the bolt 97, a nut 100 being threaded upon the lower end of bolt 97 for holding the parts in assembled position, as described. The clamp is so located that the stationary member 96 will rest above the handwheel 82 and the movable clamp member 98 will rest below the hand-wheel, so that when the handle 99 is operated the movable member 98 will be forced upwardly to clamp the wheel between it and the stationary member. When the back-stop is moved to the desired position, the hand-lever 99 is pulled outwardly to cause the cam-faces 99 and 98 to act one upon the other for securely clamping the hand-wheel between the movable and stationary members.

is a paper-holding clamping-bar, the ends of which are secured to the downwardlyeXtending guide-bars 106. The guide-bars 106 operate in vertical grooves formed in the inner faces of the machine side frames l, said grooves and the guide-bars being indicated in dotted lines in Fig. 2. To the lower ends of the guide-bars 106 are secured in any suitable manner the ends of sprocket-chains 108, which pass up over sprocket-wheels 109, journaled upon pins 109 inside of the side frames 1. The opposite ends of the sprocket-chains are connected to a counterweight W for balancing the weight of the clamping-bar and attached parts. The lower ends of guide-bars 106 are formed with dovetails 106, as indicated in Fig. 8, and horizontally-presented oblong blocks 107 are formed in their inner vertical faces with dovetail grooves to fit over the dovetailed lower ends of the guide-bars.

Countersunk screws 107 secure blocks 107 upon the dovetail ends of guide-bars 106, said blocks forming horizontal shoulders which are presented through vertical slots or guideways of the side frames for the purpose now to be explained.

110 represents rack-teeth formed in the blocks 111, which are recessed in their inner vertical faces to fit snugly over the guide-bars 106 and shoulder-blocks 107, said blocks 111 resting normally in engagement with blocks 107 and projecting through the guideways or slots of the machine side frames. The rackbars 110 are in mesh with the mutilated gears 112, keyed to the opposite ends of a transverse shaft 113, suitably journaled in the machine side frames and driven through the mechanism hereinafter described.

Before describing the power-driven mechanism for operating the clamp I will describe the foot-actuated devices for lowering the clamp independently of the power. To permit the independent lowering of the clamp, I arrange the rack bar blocks 111 (through which thepower operates) to be disconnected from the guide-bars of the clamp in the manner which I will now describe.

Secured to the under face of each of the shoulder-blocks 107 is a bracket 115, projecting outwardly and having pivoted to it at 116 an angular latch 117. This latch 117 engages a shoulder 118, formed by'the recess 119, out into each of the rack-bar blocks 111, thereby securely locking the rack-bar blocks upon the guide-bars of the clamp. A spring 120 is mounted between an arm 121 of bracket 115 and the lower face of the latch 117 for the purpose of giving the latch a spring tend ency to move into engagement with the shoulder 118. Each latch 117 is formed with a laterally-projecting lug 122, having an angular upper face 122 and a vertical opening 122", as shown in Fig. 9. A rod 123 passes up through the opening 122 of lug 122 and is formed at its upper end with a head 124, having a squared lower surface which rests directly above the inclined face 122. This rod 123 is pivoted at its lower end to a bell-crank lever 125, pivoted at 126 in bracket 127, secured -to the lower portion of one of the side frames. The free end of lever 125 carries an antifriction-roller 128, which is adapted to be with a rearwardly-projecting rock-arm 133,

which rests centrally beneath the counterweight W.

It will of course be understood that there are duplicate latching devices at opposite sides of the machine, each latching device being controlled by a cam-arm 130, having a camsurface 129, as just described. With this arrangement it will be observed that when pres sure is applied to the foot-lever 132 the initial movement of rock-shaft 4 will first cause the unlatching of the latches 117 and disconnect the rack-bar blocks from the guide-bars of the clamp. This unlatching is caused by the rocking of levers 125, which pull down upon rods 123, causing the latches to rock upon their pivots 116 by 'reason of the engagement of heads 124 with the latches out of line with pivots 116, the squared faces of heads 124 working against the inclined faces 122 of the latches. 'While the latches are being disengaged to release the clamp from its power mechanism the rock-arm 133 is moved from its lower inactive position up into engagement with the counterweight WV, so that immediately after the disengagement of said latches the continued movement of rock-arm 133 will raise the counterweight W and cause the clamp-bar to be lowered into engagement with the pile of sheets supported upon the table. As the clampis lowered the lugs 122 of the latches slide upon the rods 123, the lower shouldered ends of the guidebars moving down away from the rack-bar blocks which are supported in elevated position by the engagement of the rack-bars with the mutilated gears. When the pressure is released from the foot-lever 132, the counterweight returns the parts to their normal elevated position, the latches automatically returning into engagement with the rack-bar blocks for locking them to the guide-bars of the clamp in readiness for the operation of the machine by power.

The transverse shaft 113, carrying the gears 112, as above explained, has keyed to its outer end, as shown particularly in Figs. 3 and 4, a friction-wheel 140. The outer end of shaft 113 has bearing in the bearing 141, having bracket-supports 142 143, securely bracing and steadying. the shaft. The friction-wheel has an outer friction-surface, of leather or other suitable frictional material, (indicated in Fig. 4 at 144,) and inclosing the frictional periphery of the wheel 140 is an adjustable oscillatory driving member formed of four flanged segments 145, the opposite ends of each segment being provided with integral outwardly-extending lugs 145. Adjustingscrews 146 are threaded through suitable openings formed in the adjacent lugs 145, of the segments for adjusting the segmental driving member, causing it to bind more or less tightly upon the frictionwheel 140, as may be desired. 'Smalle'r' screws 147 are IIO sition to engage the inner faces of adjacent lugs for locking the parts in the desired adjusted position.

150 is an arm freely journaled upon shaft 113 between friction-wheel140 and bearing 141. This arm is rigidly secured at its outer end to one of the driving-member segments 145 by means of top bolts 151, passing through ears formed on arm 150 and threaded into this segment 145. The arm 150 carries an outwardly-presented journal-pin 152, upon which is ournaled the upper end of a pitman 153, extending up from a crank 155 to the crankpin 154, to which the lower end of pitman 153 is journaled. The crank 155 is secured to the outer end of a shaft 156, which extends across the machine and is suitably journaled in the side frames 1. The shaft 156 has secured to its opposite end a gear-wheel 157, which meshes with a pinion 158, journaled upon a stud 159, secured to the side frame at 160. The pinion 158 is secured o the larger gearwheel 161 and rotates with it, said gear-wheel 161 being in mesh with the pinion 21 upon shaft 22. By this arrangementthe shaft 156 is rotated once for every complete revolution of the knife-operating shaft 16. The rotation of shaft 156 carries with it the crank 155, which drives the segmental driving member 145 of the slip-clutch, causing the rotation of shaft 113 and the forcing down of the paper holding upon the pile of-sheets. The clamp is forced against the pile with any desired pressure by adjusting the driving member 145. When the clamp engages the pile with the desired pressure, which will be the limit of the frictional grip of driving member 145 upon friction wheel 140, the driving member will slip upon wheel 140 to the end of the throw of crank 155, and during this slipping action the knife is passing through the pile of sheets. Just at the completion of the downward stroke of the knife the crank 155 completes its half upward revolution and reaches the limit of its upward throw. Immediately after this the knife starts to return and the crank 155 completes its revolution, raising the clamp to its elevated position and causing the driving member to slip rearwardly upon the friction-wheel.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In a paper-cutting machine, the combination of a paper-cutting knife, suitable knifeoperating mechanism, a paper-holding clamp, a shaft suitably geared to the clamp for raising and lowering it, a friction-wheel secured to saidshaft,africtionaldriving member freely journaled upon said shaft and formed of a plurality of relatively adjustable complementary segments encircling said friction-wheel, means for relatively adjusting the segments of the driving member to regulate the frictional engagement with the friction-wheel,

and operating means connected with the segmental driving member for oscillating it.

2. In a paper-cutting machine, the combination of a paper-cutting knife, suitableknifeoperating mechanism, a paper-holding clamp, a clamp-operating shaft suitably geared to the clamp, a frictional slip-clutch mounted upon the said shaft and comprising a friction-wheel secured to the shaft, and a frictional driving member encircling the friction wheel and formed of a plurality of adjustably-connected segments, means for relatively adjusting said segments, an arm journaled upon said shaft and rigidly secured to one of said segments, and means connected with said arm for oscillating said driving member, substantially as set forth.

3. In a paper-cutting machine, the combination of a paper-cutting knife, suitable knifeoperating mechanism, a paper-holding clamp, a clamp-operating shaft suitably geared to the clamp, a frictional slip-clutch mounted upon the said shaft and comprising a friction-wheel secured to the shaft, and a driving member encircling the friction-wheel and formed of a plurality of segments, screws or bolts adj ustably connecting said segments, an arm journaled upon said clamp-operating shaft and rigidly secured to one of said segments, a crank-shaft carrying a crank, a pitman connecting the crank with said arm, substantially as set forth.

4. In a paper-cutting machine, the combination of the knife, and the knife-operating mechanism, with a pile-holding clamp,a clampoperating shaft, rack-bars driven by said shaft, latches carried by the clamp and detachably engaging the rack-bars, and means for operating said latches and for lowering the clamp independently of the rack-bars and operatingshaft, substantially as set forth.

5. In a paper-cutting machine, the combination of the knife, and the knife-operating mechanism,with a pile-ho1dingclamp,a clampoperating shaft, rack-bars detachably connect ed with the clamp, gears upon said shaft meshing with said rack-bars, latches carried by the clamp and detachably engaging the rack-bars, and manually-actuated means for simultaneously releasing said latches and lowering the clamp independently of the rack-bars and operating-shaft, substantially as set forth.

6. In a paper-cutting machine, the combination of the knife, and the knife-operating mechanism, with a pile-holding clamp, guidebars secured to the clamp and provided with shoulders, a clamp-operating shaft, rack-bars recessed to fit over said guide-bars and engage said shoulders, gears upon said shaft meshing with said rack-bars, latches carried by the guide-bars and detachably engaging the rackbars, and means for operating said latches and lowering the clamp independently of the rackbars and operating-shaft, substantially as set forth.

IIO

7. In a paper-cutting machine, the combi-, nation of acutting-knife, and knife-operatingi means, with a paper-holding clamp, a weight balancing the clamp, power mechanism for raising and lowering the clamp, said power mechanism including ashaft, gears upon said shaft, rack -bars meshing with said gears, latches carried by the clamp detachably engag ing the rack-bars, and means for manually actuating the latches and lowering the clamp independently of the power mechanism, subv stantially as set forth.

8. In a paper-cutting machine, the combination of the cutting-knife, and knife-operat ing mechanism, with a paper-holding clamp having depending guide-bars, shoulder-blocks secured tothe lower ends of said guide-bars, rack bar blocks engaging said shoulderblocks, latches supported upon said shoulderblocks, and engaging said rack-bar blocks;

and man ually-operated means for releasing sald latches and lowerlng the clamp independently of the rack-bars, substantially as set,

-i-ng mechanism, with a paper-holding clamp having depending guid e-bars, shoulder-blocks secured to the lower ends of said guide-bars, rack-bar blocks recessed to fit over said guidebars and engaging said shoulder-blocks, latches supported upon said shoulder-blocks, shoulders formed on said rack-bar blocks with which said latches engage, and manually-operated means for releasing said latches and lowering the clamp independently of the rack bars, substantially as set forth.

10. In a paper-cutting machine, the combination of the cutting-knife, and knife-operating mechanism, with a paper-holding clamp having depending guide-bars, shoulder-blocks secured to the lower ends of saidguide-bars, a balancing-weight connected with said guidebars, rack-bar blocks engaging said shoulderblocks, latches supported upon said shoulderblocks, and engaging said rack-bar blocks. and treadle mechanism adapted to release said latches, engage and raise said weight, and lower the clamp independently of the rackbars, substantially as set forth.

11. In a paper-cutting machine, the combination of a cutting-knife and its operating mechanism, with a paper-holding clamp having guide-bars, an operating-shaft carrying gears, rack-bar blocks meshing with said gears and engaging said guide-bars, latches supported upon said guide-bars and engaging the rackbar blocks, ears or lugs projecting from said ing guide-bars, an operating-shaft carrying gears, rack-bar blocks meshing with said gears taneously actuating said rods and for lower ing the clamp, substantially as set forth.

18. In a paper-cutting machine, the combination of the holding-clamp having the guidebars, the rack-bar blocks engaging the guidebars, the angular latches pivotally mounted upon the guide-bars and engaging shoulders upon the rack-bar blocks, springs sustaining the latches in engaged position, a perforated ear or lug projecting laterally from each of the latches, a headed rod passing through the openingin each of said lugs, a lever connected with the lower end of each of said rods, a camlever for actuating each of said levers, and means for lowering the clamp, substantially as set forth.

14:. In a paper-cutting machine, the combination of the holding-clamp having the guidebars, the rack-bar blocks engagingthe guidebars, the angular latches pivotally mounted upon the guide-bars and engaging shoulders upon the rack-bar blocks, springs sustaining the latches in engaged position, a perforated ear or lug projecting laterally from each of the latches and formed with an angular upper face, a headed rod passing through the opening in each of said lugs, the heads of said rods having squared lower faces or shoulders,a lever connected with the lower end of each of said rods, a cam-lever for actuating each of saidlevers, and means for loweringthe clamp, substantially as set forth.

15. In a paper-cutting machine, the combination of the holding-clamp having the guidebars, the rack-bar blocks engaging the guidebars, the angular latches pivotally mounted upon the guide-bars and engaging shoulders upon the rack-bar blocks, springs sustaining the latches in engaged position, a perforated ear or lug projecting laterally from each of,

the latches, a headed rod passing through the opening in each of saidlugs, alever connected with the lower end of each of said rods, and carrying an antifriction-roller, a cam-lever arranged to engage each of said rollers for actu ating said levers, a treadle-shaft upon which said cam-levers are mounted, and means actuated from said shaft for lowering the clamp, substantially as set forth.

16. In apaper-cutting machine, the combination of a clamp, power mechanism for operating said clamp, detachable means connecting the clamp with its power mechanism, a rock-shaft, means on said rock-shaft for actuating said power-detaching means, a weight suitably connected with the clam-p for balancing it, a lever for operating said rock-shaft,

an arm extending from said lever beneath the counterweight for raising it, substantially as set forth.

'17. In a paper-cutting machine, the combination of a clamp, power mechanism for operating said clamp, detachable means connecting-the clamp with its power mechanism, a rock-shaft, means on said rock-shaft for actuating said power-detaching means, a weight suitably connected with the clamp for balancing it, levers journaled upon said shaft and connected with said weight for guiding it, a foot-lever for operating said rock-shaft, an arm extending from said lever beneath the counterweight for raising it, substantially as set forth.

18. In a paper-cutting machine, the combination of a cutting-knife, and operating mechanism therefor, a pile-holding clamp, and operating mechanism therefor, a power-shaft, a clutch upon the power-shaft through which motion is communicated to the operating mechanisms of the knife and clamp, a rock-shaft adapted to throw said clutch into and out of action, a thrust bar operatively connected with said rock-shaft, a cam mounted upon a rotating part of the machine, and adapted to actuate said thrust-bar for throwing out said clutch, and a manually-operated device adapted to engage said thrust-bar and disengage it from said cam, substantially as set forth.

19. In a paper-cutting machine, the combination of a cutting-knife, and operating mechanism therefor, a pile-holding clamp, and operating mechanism therefor, a power-shaft, a clutch upon the power-shaft through which motion is communicated to the operating mechanisms of the knife and clamp, a rock-shaft adapted to throw said clutch into and out of action, a rock-arm on said rock-shaft, a thrustbar pivotally connected with said arm, a cam mounted upon a rotating part of the machine, and adapted to actuate said thrust-bar for throwing out said clutch, and a manually-operated device adapted to engage said thrustbar and move it on its pivot to disengage it from said cam, substantially as set forth.

20. In a paper-cutting machine, the combination of a cutting-knife, and operating mech anism therefor, a pile-holding clamp, and operating mechanism therefor, a power-shaft, a clutch upon the power-shaft through which motion is communicated to the operating mechanisms of the knife and clamp, a rock-shaft adapted to throw said clutch into and out of action, a rock-arm on said rock-shaft, a thrustbar pivotally connected with said arm and movable laterally upon its pivot, a guide supporting the thrust-bar, a cam mounted upon a rotating part of the machine, and adapted to actuate said thrust-bar for throwing out said clutch, and a manually-operated lever adapted to engage said thrust-bar and disengage it from said cam, substantially as set forth.

21. In a paper-cutting machine, the combination of the knife, and its operating mech-' anism, with the clamp and its operating mechanism, a power-shaft having a clutch, a clutchactuating rock-shaft, a brake-band encircling 7 one member of said clutch, a lever to which one end of said brake-band is connected, a

spring acting upon one end of said lever for brake, substantially as set forth.

22. In a paper-cutting machine, the combination of the knife, and its operating mechanism, with the clamp, and its operating mechanism, a power-shaft having a clutch, a clutchactuating rock-shaft, a brake-band encircling one member of said clutch, a lever to which one end of said brake-band is connected, an

adjustable device to which the opposite end of v said brake-band is connected, a spring acting upon one end of said lever for applying the brake, a cam-shoe supported from said rockshaft in position to engage the opposite end of said lever for releasing the brake, and means for actuating said rock-shaft, substantially as set forth.

TALBOT C. DEXTER.

Witnesses:

WM. P. HAMMOND, WM. E. KNIGHT.