US 1314291 A
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Description (OCR text may contain errors)
J. D. WALLACE.
APPLICATION man JULY 12. 1918.
Patented Aug. 26, 1919.
3 SHEETS-$HEET I- ZOZZ71Q65 J. D. WALLACE.
APPLICATION FILED JULY I2. 1918.
1,314,291. Patented Aug. 26, 1919.
3 SHEETSSHEET 2.
J. D. WALLACE.
APPLICATION HLED JULY 12. I918.
1,3 14,29 1 Patented Aug. 26, 1919.
3 SHEETSSHEET 3.
71055: BY W/ W ATTORNEYS.
UNITED STATES PATEN T OFFICE.
JOHN D. WALLACE, OF CHICAGO, ILLINOIS, ASSIGNOR 1'0 J. D. WALLACE & 00., OF
CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.
Specification of Letters Patent.
Patented Aug 26, 1919.
To all whom it may concern:
Be it known that I, JOHN D. WALLACE, citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Sawing Appliances; and I do hereby declare the following to be a full, clear, and exact description of the 1nvention, such as will enable others skilled in the art to which appertains to make and use the same.
My invention relates to sawing appliances, and more particularly to novel means for adjusting a circular saw with reference to the saw-table, for effectively guarding the saw, and for deflecting the refuse stock to avoid its being caught by the saw and thrown against the operator. In one of its general aspects, my invention aims to permit various vertical and angular adjustments of the saw without tilting or in any way changing the posit-ion of the saw-table, thereby enabling the operator to work constantly in substantially the same position and likewise maintaining the desired lighting regardless of the adjustments of the saw. In another aspect, my invention relates to guards for circular saws, and aims to provide a guard which will be equally effective regardless of the height or angle at which the saw table may be adjusted with respect to the saw, which will automatically be forced out of its guarding position by the stock when the latter is being sawed and which will automatically return to its initial guarding position after each sawing operation; which will effectively guard the periphery as well as the side of the teeth of the saw, and which will automatically deflect the waste part of the stock when the guard is returning to its initial position. Furthermore, my invention aims to provide an adjustable saw mounting, as well as a guard and a mounting for the latter, which will all be free from complications, cheap and easily assembled. It also aims to reduce the friction between the stock which is to be sawed, and the portion of the guard engaged thereby, so as to minimize the resistance offered by the guard during the sawing operation. Furthermore, my invention aims to provide a guard which will be continuously disposed close to the saw and which will automatically adjust itself to an effective guarding position when the position of the table is shifted with respect to the saw. Still other objects will appear from the following specification, and from the accompanymg drawings, in which- F1gure 1 is a fragmentary vertical se ctlon through a guarded circular sawing ap+ phance embodying my invention.
Fig. 2 is a vertical section taken at right angles to that of Fig. 1, from the line 2-2 of thelatter and with the saw and the sawclamping washers omitted.
Fig. 3 1s a plan view corresponding to Fig. 2.
Fig. 4 is an enlarged vertical section showing the arrangement of the guides for the cradle which supports the motor, guard and saw.
Fig. 5 is a detail of the shaft end of the guard.
Fig. 6 is a fragmentary front elevation of the saw, drawn on a smaller scale than Fig. 1 and showing the saw tilted with respect to the table. a
Fig. 7 is a fragmentary section, drawn on a smaller scale than Fig. 2 and showing the guard in both of its extreme operative positions when the saw is lowered from its position of Fig. 2 with respect to the table.
Flg. 8 is a fragmentary detail showing a drive pulley as substituted for the motor of Figs. 1 and 6.
Fig. 9 is afragmentary vertical section showing the manner in which the stop element on the guard underhangs the Waste portion of the stock and deflects the latter.
Fig. 10 is a fragmentary view of the forward end of a guard showing another shape of stop element.
Heretofore, it has been customary in appliances of this general class either to provide only for a relative vertical adjustment of the saw and the saw-table (thereby affording different depths of cut of the saw, but not permitting cuts to be made other than at right angles to the top of the sawtable), or to tilt the table itself while maintaining the arbor of the saw horizontal.
This tilting of the table is objectionable for many reasons, one being the difference in position which it requires the operator to take'a'ccording as the table is shifted, thereby making him work at a disadvantage. Another objection is the interference of the tilting with the proper light upon the work; also, the tendency of the wood to slide down an incline, thereby causing some part of the 7' a tilting of the table necessarily limits the size of the stock which can be handled upon the saw table to such lengths as will not strike the floor at the bottom of the incline formed by the top of the saw table, thus preventing the making of angular cross-cuts in long ieces of stock. So also, the tlltlng of the ta le has generally interfered with the effective use of guards which were otherwise serviceable when a tilting of the table was not attempted.
In overcoming these and other objections to the appliances heretofore in use, I employ va stationary table which is contlnu ously maintained in a fixed and horlzontal position, thereby permitting the operator to work continuously in the same position, and with the same lighting arrangement, and to make cross-cuts in stock of any desired length. Then I provide a mounting for the saw and preferably a joint mounting for the saw, the guard, and a driving element connected to the saw; and/I provide simple means for adjusting this joint mounting so as to raise or lower the saw with respect to the table, and so as to tilt the saw at any desired angle. I also rovide means associated with the guard or automatically returning the guard to its initial guarding position when the saw has formed its cutting operation, for automatically shift ng this initial position of the guard accordlng tothe adjusting of the saw with respect to the saw, and for deflecting the waste part of the stock during the return movement of the guard to its initial guarding position.
For example in Fig. 1 the.saw table 1. (which is mounted on legs or other su porting means not shown in the drawmgs? carries' a box type of fence 2 and has a slot extending parallel to this fence. This slot is wide enough for the pro ecting therethrough of a circular, saw. 3 and of the guard 4. The saw 3 is mounted on an arbor 5 journaled in a bearing 6, whlch bearing is also shown as carrying the frame of an electric motor 7 having its armature directly connected to the arbor 5. The bearing 6 and the parts thus carried thereby are mounted on a cross-bar 8 sliding upon guide rods 9 on a cradle 10, and a swivelheaded screw 11 interposed between the cradle 10 and the cross-bar 8 (or the bearing 6 which is rigid with respect to the said cross-bar) enables the bearing 6 and the parts carried thereby to be adjusted vertically with respect to the cradle.
The cradle 10 has forked ends 12 straddling segmental supports 13 carried by the table 1 and substantially coaxial with the line along which the circular saw 3 intersects the upper surface of the table 1. The cradle 10 is connected by suitable means, such as a link 14 and a swivel-headed screw 15, with a rigid part 26 of the frame work of the table (as shown in Fig. 6), so that the cradle may readily be rocked on its guides about the said axis, thus tilting the saw to any desired angle, as for example that of Fig. 6. With the parts arranged as described, it will be obvious that the arbor carried by the saw may be moved either toward or away from the table top 1, thereby varying the distance to which the saw 3 projects above the table; also, that this arbor may be adjusted independently of the aforesaid adjustment, to assume varying angles with the table top.
To guard the exposed portion of the saw, I pivot a swinging guard 4 upon the bearing 6, thereby continuously maintaining the guard in proper concentric relation to the saw arbor regardless of the height or angle to which the latter is adjusted with refer* ence to the saw table. The guard 4: desirably consists of a substantially segmental sheet metal punching equipped at its periphery with a flange 35 overhanging the peripheral edge of the saw 3 and directed toward the fence 2. At its inner end, the guard 4 desirably has an offset portion terminating in an annular flange 16 which flange houses and is secured to a ring 17 journaled upon the end of the bearing 6 which faces the saw. This end is desirably turned to a diameter matching the bore of the ring 17 and also is equipped with an annular groove 18 spaced from the end of the said'bearing portion and adapted to receive radially inwardly extending lugs 19 upon the said flange 16 of the guard, as shown in Figs. 1 and 5.
The flanged end of the guard also carries an ear 20 affording attachment for a spring 21 connecting the guard with a pin mountedon the cross-bar 8, as shown in Figs. 2 and 7. At its forward end, the guard is equipped close to its periphery wlth a suitable nose or projection extending laterally beyond the slot in the table and hence adapted to'engage the upper surface of the table and thereby limit the swinging of the guard in one direction. For this purpose, I desirably employ a roller 22 as shown in Fig. 3, and I widen the rear end of the slot so as to permit the ready passage of the roller through the same when the guard is swung back as shown in dotted lines in Fig. 7. This roller is desiraby comparatively small in diameter and substantially flush with the flange 5 of the guard, the function of the roller being to reduce the friction between the forward end of the guard and the stock which engages this end when it is being slid upon the surface of the table toward the saw. Moreover, the spring 21 preferably is so arranged as to increase in effective resistance to the rearward swinging of the guard with the movement of the latter out of its guarding position, so that it will offer a maximum return efi'ort when the guard is swung entirely below the table, and will offer a minimum resistance at the initial engagement of the guard with the stock which is to be sawed. For this purpose, I may use a spiral spring so placed as to wind partly around the offsetting portion of the guard, as shown in Figs. 2 and 7. However, I do not wish to be limited to this or other details of the construction and arrangement here disclosed, it being obvious that the same might be modified in many ways without departing from the spirit of my invention. Thus, while Figs. 1 and 6 show the saw 3 as driven by an electric motor 7 supported entirely by the crossbar on the cradle, other driving means might be substituted, such as a drive pulley 23 connected by a belt 24 to a suitably disposed source of power, substantially as indicated in Fig. 8.
WVith the guard arranged as described, it will be obvious that, since the guard is mounted concentric with and close to the saw, the guard will continuously be su ported in desirable operative relation to t e saw, regardless of the height or angle at which the saw is adjusted with respect to the saw table. Consequently, the operator does not need to make any separate adjust ment for the guard, but merely moves the screws 11 and 15 to afford the desired cut-.
ting adjustment for the saw. Then the spring 21 and the roller 22 cooperate with the pivoted mounting of the guard to maintain the latter in proper operative position.
. That is to say, when the saw arbor is lowered with respect to the table, the engagement of the roller .22 with the top of the table automatically swings the segmental guard backward from the position of Fig. 2 to that of Fig. 7, or to a point corresponding to the lowering of the saw arbor. When the saw is not in use, the spring 21 continually holds the roller 22 upon the upper surface of the table forwardly of the saw, and does so regardless of any tilting of the saw, as will be evident from Fig. 6. Then when the stock 24 which is to be sawed is slid along the table, this stock first engages the revoluble nose or roller 22, thereby swinging the guard out of the way against the tension of the spring 21 and eventually forcing the roller 22 below the top of the table 1 as shown in Fig. 8. However, as soon as the rear end of the stock has cleared the saw and moved past the roller 2-2, the spring 21 will automatically return the guard to its initial position.
To reduce the inertia of the guard, I desirably make the latter of rather light material, and I may further lighten the same by perforations as shown in the drawings, thereby making the guard quite sensitive, in order that it may be quickly returned to ts initial guarding position when the cut s finished or in case the stock is withdrawn in the event of an accident. Also, I desirably place the nose or other movement-limitingpro ection carried by the guard upon the side away from the saw, so that when the stock passes over the guard and depresses the latter as shown in dotted lines in 1g. 7, this nose or projection will underhang only the waste portion of the stock. For this same reason, I desirably do not carry the flange 35 on the guard beyond the teeth of the saw, though it may terminate flush with these teeth as shown in Fig. 1. Consequently, when the stock has been fed sufficiently along the table for the saw to complete its cut, the continued pressure of the operators hand upon the portion of the stock guided by him will not interfere with the returning of the guard to its initial guarding position, thus protecting the operator between the time when the cut is finished and the time when the stock is moved entirely clear of the saw. On the contrary, the detaching of the waste part of the stock from the part guided and depressed by the operator will permit the upward thrust of the spring-pressed guard to raise and deflect the waste portion of the stock'(as shown for.
example in Fig. 9), thereby moving this waste portion out of the way, so that it cannot catch in the teeth of the saw and possi'bly cause accidents.
Tofacilitate the attaching of the guard to the end of the bearing on which it is journaled through the ring 17, I desirablv cut away portions of the end of the bearing on which this ring is journaled, as shown in Fig. 7, thereby affording longitudinal grooves through which the lugs 19 may be moved into alinement with the peripheral groove 18 on the hearing when the guard is swung so far out of its position of Fig. 7 that the left hand lug 19 of that figure alines with the right hand groove in the bearingof the same figure. This is done before the sprin 21 is attached to the guard, the longitudinaI grooves in the end of the bearing being preferably so narrow that the lugs 19 will not move out of the groove 18 during the swinging of the guard throu h its normal range of movements between its operative and inoperative positions.
However, while I have shown and described the particular mountin of the guard, and have described the pro ection or nose upon the guard as a roller, I do not wish to be limited to these or other particulars here disclosed. For example, the nose might consist of a non-circular revoluble element as shown in Fig. 10, thus affording a flat bearing on the top of the table, or such a stop clement might be riveted firmly instead of being revolublc. Likewise, it will be obvious that even with the use of a rcvoluble stop and stock-engaging element, a continued feeding of the stock causes the latter later on to engage part of the guard itself.
I claim as my invention:
1. A saw-table, a circular saw, driving means for rotating the same, a guard normally disposed for guarding the exposed portion of the saw; a unitary mountlng for the saw, driving means and the guard; and means for adjusting the unitary mountmg with respect to the saw-table without disturbing the operative relation of the driving means and the guard to the saw.
2. In combination with a saw-table having a slot therein, a supporting member disposed under the saw-table and mounted on the latter for rocking movement about an axis disposed within said slot and parallel to the latter, means for holding thesupporting member in any posit1on to which it may be rocked, and cooperatingmembers carried by the supporting member and 111 cluding a circular saw and a guard in operative relation thereto, both the saw and the guard normally projecting through the sald slot, the guard being adapted to be moved out of its projecting position by the feeding of the stock to the sa v 3. In combination with a saw-table having a slot therein; a group of members including a saw arbor, a circular saw fast on the arbor, and a guard movable w th respect to the saw; an arcuate guide dlsposed below the table and concentric with an axis disposed in the slot and longitudinal of the latter; and a mounting movably earned by the guide for supporting the sand group of members in a position permitting both the saw. and the guard to project through the slot. I
4. Mechanism as per claim 3, in combination with means for moving the said group of members with respect to the mounting to vary the extent to which the saw projects through the slot.
5. A saw-table having a slot, a cradle mounted for rocking movement about the slot as an axis, a bearing carried by the cradle and movable with respect to the cradle radially of the said axis, separate means for tilting the cradle and for moving the bearing with respect to the latter, and a group of cooperating members earned by the bearing and including a c1rcular saw and a guard pivoted coaxially with the saw, both the saw and the guard normally projecting through the slot, the ard including a portion peripherally over anging a portion of the teeth of the saw and adapted to a saw-table having a jecting through the slot, an arbor carrying the saw, a guard normally guarding the projecting portion of the saw and adapted to be moved out of its guarding position by the feeding of the stock to the saw, means for permitting a simultaneous tilting of the saw and guard with respect to the table, and means operatively unaffected by the said tilting for normally maintaining the guard in its said guarding relation to the saw.
8. A saw-table, a circular saw, a segmental guard mounted concentric therewith and movable about the axis of the saw; means for simultaneously moving the saw and guard toward or from the table, means for simultaneously tilting the saw and guard with respect to the table, and means responsive to the position of the saw with respect to the table for moving the guard about the axis of the saw.
9 In an appliance of the class described, a clrcular saw, an arbor carrying the same, a bearing for the arbor having a peripheral groove and a substantially longitudinal slot leading thereto, and a guard pivoted on the bearing and having a portion projecting mto the groove and adapted to be inserted in the latterv through the said slot.
10. In a sawing appliance, a circular saw, an arbor carrying the same, and means for supporting the arbor and guarding the saw: the said means including as onemember a bearing having a substantially cylindrical end portion, and as another member a guard having a substantially cylindrical portion larger than the aforesaid portion, a ring interposed between the cylindrical portions of the said two elements and secured to one thereof, and means associated with the said elements for preventing a relative movement thereof in directions longitudinal of their cylindrical portions.
11. A circular saw, a guard for the same, slot through which both the saw and the guard project, means for simultaneously moving both the saw and the guard with respect to the saw-table, and means responsive to the said moving for maintaining the forward tip of the guard substantially in a predetermined relation to the most forward exposed saw tooth.-
12. The combination with a saw-table havmg a slot and a circular saw projecting through the slot of a guard substantially concentric with the saw and also projecting through the slot and presenting a nose normally disposed for engaging the stock in advance of the saw, means for simultaneously adjusting the positions of the axis of the saw and of the taining the nose of the guard in its said position regardless of the said adjustment.
13. In combination, a circular saw, a spindle carryin the same, a bearing for the spindle having an annular groove near the end facing the saw, and a saw uard havin a portion socketed in the sai groove an having another portion overhanging the actively disposed teeth of the saw.
14. In a sawing appliance, a table having a slot, a circular saw projecting through the slot, and a ard pivoted concentrically with the saw an also projecting through the slot and having a segmental edge portion overhanging a part of the periphery of the saw, the guard having a nose normally overhanging one side of the slot forwardl of the saw,. and the rear portion of'the s ot being widened to permit the passage of the nose therethrough when the guard is moved out a of its operative position.
15. A circular saw, a guard mounted concentric therewith and movable independently of the saw about their common axis, a
table having a slot through which the sawand guard both project, yielding means for normally holding the guard in protective relation to the portion of the saw projectin through the slot while permitting the guar to be moved out of its said relation by the feeding of the stock to the saw, and a projection on the guard out of alinement with a part of the slot through which the normally guarded art of the saw projects, the slot having a ateral enlar ement at its rear end to permit the projectlon to pass below the top of the table and to underhang the waste portion of the stock.
16. In a sawing appliance, a stationar table having a slot, a saw projecting throng the slot an arbor carrying the saw, means supporting the arbor and permitting a tilting thereof with respect to the table, means normally guarding the exposed periphery of the saw and adapted to be moved out of its guarding position b the feeding of the stock to the saw, and means for returning the guarding means to their normal position when the stock has passed the saw, the guarding means having a portion underhangin only the waste part of the stock and dispose for moving only said waste part away from the saw during the returning of the guarding means.
17. A sawing appliance as per claim 16, in
ard with respect to the table, and means or normall mainwhich the refuse-deflecting means also serve as a stop for limiting the return movement of the guarding means.
18. In a sawing appliance, a table having a slot, a saw projecting through the slot, a saw-guard normally guarding the exposed periphery of the saw and adapted to be moved out of its guarding position by the feeding of the stock to the saw, and means for automatically returning the guard to its guarding position when the stock has passed the saw, the guarding means including a portion disposed for laterally deflecting the waste part of the stock during the return movement of the guard.
19. A sawing appliance as per claim 18, in which the guard also operates throu h the slot, and in which the waste-stock de ectmg means normally engage the table to limit the return movement of the guard.
20. In a sawing appliance having a saw protected by a movable guard, single means carried by the guard for limiting the movement of the guard in one direction and for laterally deflecting the waste portion of the stock during the movement of the stock in the said direction.
21. In a sawing appliance, a table having a slot, a saw and a guard therefor both normally projecting through the slot, a guard mounting permittin the guard to be moved to a position entire y below the top of the table by the stock fed to the saw, yieldlng means continuously resisting the said movement of the guard, the guard hav ng a portion underhanging the Waste portion of the stock when the guard is moved to its said position below the top of the table.
22. The combination of a saw-table hfl,\' ing a slot, a circular saw rojectm through the slot, a movable guar mounte substantially concentric with the saw and also projecting through the slot and having a portion normally engaging the table to 1m1t the movement of the guard, in one directlon, yielding means continuously tending to move the guard in the said direction, and means for tilting the common axls of the saw and guard with respect to the table without operatively disturbing the said relations of the aforesaid elements.
23. In a sawing appliance, a saw table having a slot; a saw and a guard for the saw concentric with the latter, both project ng upwardly through the slot; and cooperat ng means for raising or lowering, and for tilting both the saw and the guard simultaneously while maintaining the guard in operaive relation to the saw.
Signed at Chicago, Illinois, July 6th, 1918.
JOHN D. WALLACE.