US1864266A - Tack machine - Google Patents

Description

June 21, 1932. G. B. BAKER ET AL TACK MACHINE Filed Oct. 24, 1927 2 Sheets-Sheet l I. .l T

TACK MACHINE Filed Oct'. 24. 1927 2 Sheets-Sheet 2 i 22 0/2 .14 01 T i 47 f la; id

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Patented June 21, 1932 UNITED STATE S PATENT OFFICE GEORGE IB. BAKER, HERBERT B. BAKER, AND EDWARD C. BAKER, OF BROCKTON, MAS- SACHUSETTS, ASSIGNORS, BY MESNE ASSIGNMENTS, .IIIO GEORGE -B. BAKER AND EDWARD C. BAKER,-OF BROCKTON,.MASSACHUSETTS, AS SURVIVING JOINT TENANTS I TACK MACHINE Application filed October 24, 1927. Serial No. 228,138.

This invention pertains to tack and nail making machines and relates more particularly to means for feeding the blanks or tack strips to the cutting instrumentalities. In our Patent No. 1,555,933 dated October 6, .1925, we have disclosed a tack machine of highlv eflicient and useful character, which, in common with other known types-of tack machines emplovs intermittently actuated feed rolls for advancing the blanks or Stack strips toward the cutting instrumentalities. Such an arrangement of feed rolls, particularly when used in the Specific environment disclosed in our aforesaid patent, constitutes veryeflective and desirable means for feeding the blanks, since the use of such rolls makes it possible to avoid the complications attendant upon endwise reciprocation of the blank holding barrel (as is common in certain types of machines) while as disclosed in our aforesaid patent, such rolls also perform the function of detector means in a verysatisfactorv way.

It has been the common practice to :turn such feed'rolls in the forward or work advancing direction by positive means, for example,

a cam, eccentric. or crank which moves the rolls a fixed and predetermined distance at each successive actuat1on,'prov1s1on somet mes beingmade for adiusting this distance.

While this type of mechanism, when accurately adiusted. should produce (intheorv at least) substantially perfect results, it does not accurately accommodate itself to slight changes in conditions of operation and does not always attain the theoretical perfection of operation which might be expected. Thus slight variations in the material operated upon or in the operation of the various moving parts of the machine are sufficient to interfere with the "accuracy of the feed, it being noted that in the formation of tacks of small size the feed movement is of the order of a few hundredths of an inch.

In accordance with our present invention we avoid the above difiiculties and eliminate substantially allimperfect work arising from the above causes, although retaining the feed rolls with their advantages, but so actuate these rolls as toqcause the blank to be crowdi ed forward with substantially continuous pressure toward the cutting position just before and during the entire cutting operation. This crowdingforward of the blank is not dependent upon the action of a reciprocating part of uniform'throw, but is substantially c tinuous, except when the barrel is turning or oscillating, and jams the forward end of the blank forcibly againstthe usual limiting stop so that as the cutters are actuated they i "vention which is illustrated by wayof example in the accompanying drawings in which: Fig. 1 is aside elevation of a tack machine of the tvpe above referred to and having the present improvements applied thereto;

Fig; 2 is a fragmentary side elevation, to larger scale, partly in section, showing the forward portion of the blank supportingbar- :rel and associated parts,

F ig. -3 is a fragmentary plan view, partly. in section on the line 33 of Fig. 2; F ig. 4 is a fragmentary verticalsection on the line 4 4 of Fig. 3; and

Fig. 5 is a vertical section on the of Fig. l. c 5 Referring to the drawings thenumeral 1 indicates the supporting frame of a tack machine of the type referred to. This frame is provided with bearings for the main shaft having the hand wheel 2 and carrying the usual cams, cranks, and other devices for actuating the operating parts of the machine, including the movable cutters 5 and 6 (Fig. 2) and the movable limiting stop 7... The frame 1 also supports an anvil block 3 carrying the fixed or ledger blade 4, the latter being provided with a diagonal cutting edge in the usual manner. Resilient guards or. guides 9 are supported upon the'anvil block 3 by means of brackets 11, these guards coop erating in usual manner to position the blank line 5- 5 laterally as it is advanced toward the cutters.

20 carried by a block 21 which is carried by the table 12. A cross bar 22 is secured to the upper ends of the posts 19 and constitutes an abutment for a spring (not shown) whose lower end engages a yoke member 27 bearing upon the upper surface of the barrel 14.'

This spring tends to hold the barrel downwardly with its free lower extremity engaging the upper surface of the anvil block but permits the barrel to rise slightly as it is oscillated during the operation of the machine.

Straps 28 and 29 constitute the means for oscillating the barrel as is usual in machines of'this type. These straps are wound in opposite directions about the barrel, and their lower ends are secured to oppositely directed arms of a lever 30 fulcrumed upon the extension 13. This lever is rocked at suitable intervals by means of a link 32 actuated by a cam or crank carried by the main shaft of the machine.

A yoke 38 is secured to the bracket 17 and supports an elongated guideway 39 forming a part of the automatic replenishing means which is fully described in our aforesaid patent and which forms no essential part of the present invention.

Near its lower end the barrel is furnished with an extension or sleeve 40 (Fig. 2) which carries a box-like casing 40 which is preferably open at its top and bottom and which has a passage aligning with the passage through the main part of the barrel. The

casing 40 is provided with journal openings for a transverse shaft 41 upon which is mounted a knurled feed roll 42 which cooperates with a feed roll 43 mounted upon a second transverse shaft 44. Preferably the upper shaft 41 is journaled in movable bearings and is pressed toward the other shaft by means of a spring or springs'as more fully disclosed in our aforesaid patent. Also there is preferably associated with the upper shaft or its bearings a movable electrical contact 80 adapted to engage an insulated contact ring 80 mounted on the barrel, all as fullydescribed in our patent above referred to.

The shafts 41 and 44 are provided with intermeshing gear wheels 45 and 46 which constrain the shafts to move at substantially the same speed in opposite directions. One of these shafts, as here shown the shaft 41, is provided at one end with a ratchet wheel whichactuates the feed rolls.

47 fixedly secured to the shaft and constituting means for driving the feed wheels. A driving pawl 48 (Fig. 4) engages the teeth of this ratchet wheel, being pressed into engagement with such teeth by means of a sprmg 52. i This pawl 48 is pivotally supported upon a pawl carrier 49 which slides longitudinally in suitable guides 50 and 51 projecting from the side of the casing 40 A spring 53, connected with the pawl carrier, tends to move the latter to the left as viewed in Figs. 2, 3 and 4 that is to say, in a direction such as to retract the pawl and cause it to engage a fresh tooth of the ratchet wheel. Preferably the pawl carrier 49 is of angular section or othersuitable shape to prevent it from turning in its bearings and is provided at its rear end with an anti-friction roller 54.

The block 21 is furnished with a journal opening for 'a transverse shaft 55 constituting the axle of an actuator lever having the downwardly extending arm 56. A tension spring 57 is secured to the lower end of the arm 56 and to a fixed pin 58- conveniently mounted upon the extension member 13.

The actuator lever also comprises a pair of upwardly extending pusher arms 59 and 60 disposed'respectively at opposite sides of the barrel 14 and so positioned that during the cutting operation one or the'other of these arms engages the anti-friction roll 54 of the pawl carrier. The arms 59 and 60 are substantially'upright and if desired their upper ends may be bent slightly as" indicated at 60 although this is not essential. The actuator lever also has an upwardly extending arm 61 which is pivotally connected at its upper end to a link 62 extending to a member 63 which is rocked by a cam or other suitable element carried by the main shaft.

i The forward end of the casing 40 supports a bracket 64 carrying the nose piece comprising the spaced upper and lower members 65 and 66 constituting the means for guiding the blank B near the cutting point.

The electrical contact elements 83 and 86 shown in our aforesaid patent are in this instance moved to the left of the bracket 20 as viewed in Fig. 1 to avoid interference with the feed roll actuating means described, but

such contacts function in the same way as described in our patent.

The operation of the machine is in general similar to that of tack machines of this type and more specifically as described in ouraforesaid patent except for the mechanism As indicated in Fig. 2 the parts are in position for the downward movement of the cutters 5 and 6. -At this time the forward end of the blank B ment with the roll 54 of the pawl carrier by the action of the spring 57. This spring is long and strong and tends to exert a constant pressure upon the pawl carrier, urging the latter in a forward direction or to the right,

as Viewed in Fig. '2, thus tending to turn the V ratchet wheel 47 through an arc of large extent. If free to do .so the ratchet wheel would turn and with it the feed rolls to an extent much greater than necessary to advance the blank B the proper distance for cutting, but

tially constant pressure, against the stop.'

By reason of this normally exerted force the blank is held firmly in proper position durmg cutting.

As the barrel 14: must be oscillated through 180 between successive cutting operations,

and as the pawl carrier turns bodily with the barrel, the roll 54 moves out of engagement with the arm 60 as the barrel starts to oscillate. As soon as the roll 54 disengages the arm 60, the spring 53 is free to retract the pawl carrier so that the pawl may engage a fresh tooth of the ratchet wheel. This rearward movement of the pawl carrier, as well as such forward movement of the actuator lever as may be permitted after the pawl carrier has disengaged the arm 60, so positions the parts that as the pawl carrier approaches the dotted line position indicated at 54' in Fig. 3, it would normally contact with the end of the arm 59 of the actuator lever. To avoid such contact we have provided the lever with the arm 61 and the actuating link 62, and as the barrel nears the completion of its oscillation, the arm 61 is rocked so as to swing the actuator lever and move the arms 60 and 59 to the dotted line position shown in Fig. 2. In this position the roll 54 is free to'swing down into its lowermost position, whereupon the arm 61 is permitted to rock backwardly, causing the arm 59. to engage the :roll, thus reapplying pressure to the pawl carrier and feeding the blank forwardly with substantially a constantly maintained force against the limiting stop.

The above operations are repeated at each successive oscillation of the barrel, and it is evident that, except during the time when the barrel is turning, the action of the spring 57 through the intervening parts is to press the blank forwardly with substantially constant force prior to and during the entire cutting operation. All back-lash between the blank and the cutting instrumentalities is thus avoided, and since the operative movement of the actuator lever is not dependent upon any reciprocating element having a definite length of throw, the mechanismis capable, withoutadjustment, of feed- ,tending to move the ing the blank to "the proper extent .and without reference to the size .of the piece to be removed from the end of the blank.

By the provision of the mechanism above described we have been able to eliminate sub- 1 stantially all waste due to improper feedingand to obtain in many casesperfect, that is to say 100%, production. While we have shown .a preferred embodiment of our invention, we contemplate thatisimilar result-s may be obtained by mechanism of somewhat different character but operating upon the same general principle, and we wish it to be under- :stood that it is\within the scope of our invention to make such changes in proportion and relative arrangement of parts and to substitute such equivalents as fall Within the scope of the appended claims.

We claim:

1. A tack machine means for supporting a blank, intermittently acting feed rolls for advancing the blank step bystep, cutting means, :and stop means for lim1ting advance of the blank, said machine comprising means tending to turn the feed rollsintermittently through successive arcs each in excess of the. amount necessary to engagethe end .of-the'blank with the stop means.

. 2. A tack machine of the type having means for supportin a blank, feed rolls for advancing the blani, cutting means, and stop means for limiting advance of the blank, said machine comprising means normally exlelrting yielding force for turning thefeed ro' s.

3. A tack machine of the type having means for supporting a blank, feed rolls for advancing the blank, cutting means, and'stop means for limiting advance of theblank,said machine comprising spring-means normally exerting force for turning the feed rolls to advance the blank into engagement with the stop means.

4. A tack machine of the type having means for supporting a blank, feed rolls for advancing the blank, cuttingmeans, and stop means for limiting advance of the blank, said machine comprising spring means nor mally tending to turn the feed rolls an amount in excess of that'necessary to engage the blank with the stop means. i

5. A tack machine of the type having means for supporting a blank, feed rolls for advancing the blank, cuttingmeans, and stop means for limiting advance of theblank, said machine comprising a pawl and ratchet. for turning the'feed rolls, and a spring normally pawl and thereby to turn the feed rolls. i s V 6. A tack machine having. in combination with an oscillating and non-reciprocating prising blank advancing means disposed near:

of the type having the delivery end of the barrel, said feed device normally exerting resilient pressure while the barrel is stationary to advance a blank along the barrel'into engagement with the stop means and being adapted to advance a blank of unlimited length.

7. A tack machine having a combination with an oscillating and non-reciprocating tubular blank supporting barrel into one end of which the blank is introduced and from the other end which the blank is dewith an oscillating and non-reciprocating,

tubular blank supporting barrel, cutting means, stop means, and feed rolls adjacent to the delivery endv of the barrel normally exerting a continuous force during intervals between successive oscillations of the barrel causing-the end of the blank to press forcibly against the stop means.

9. A tack machine of the type having an intermittently oscillating tubular blank supportingbarrel, feed rolls for advancing a blank along the barrel, cutting means, and stop-means for limiting the advance ofthe blank, said machine comprising means normally exerting yielding force while the barrel is stationary tending to turn the feed rolls, said force exerting means being inoperative during a part at least of the oscillatory movement of the barrel.

10. A tack machine of the type having an intermittently oscillating blank supportlng barrel, feed rolls for advancing a blank along the barrel, cutting means and stop means for limiting advance of the blank, said machine comprising spring means normally tending to turn the feed rolls, said spring means being inoperative during a part at least of the oscillatory'movement of the barrel.

11. A tack machine of the type having an intermittently oscillating blank supporting barrel, feed rolls for advancing a blank along the barrel, cutting means, and stop means for limiting advance of theblank, said machine comprising a ratchet wheel connected to one of the feed rolls, a pawl for driving the ratchet, and an actuator for the pawl normally exerting continuous force, during intervals between successive oscillations of the barrel, in a direction to move the pawl for turning the ratchet. a

12. A tack'machine of the type having an intermittently oscillating blank supporting barrel, feed rolls for advancing a blank along the barrel,cutting means, and stop means for limiting advance of the blank, said machine comprising a ratchet and a ratchet-driving pawl for turning the feed rolls, and an actuator for the driving pawl normally exerting continuous force while the barrel is stationary in a direction for operatively moving the pawl, said actuator being inoperative during a part at least of the oscillating movement of the barrel.

13. A tack machine of the type having an intermittently oscillating blank supporting barrel, feed rolls for advancing a blank along the barrel, cutting means, and stop means for limiting advance of the blank, said machine comprising a ratchet and a ratchet-driving pawl for turning the feed rolls, a movable carrier for the pawl, an actuator normally engaging said pawl carrier and tending to move the latter so as to turn the ratchet wheel, and means for disengaging the actuator from the pawl carrier as the barrel oscillates.

14;. A tack machine of the type having an intermittently oscillating blank supporting barrel, feed rolls for advancing a blank along the barrel, cutting means, and stop means for limiting advance of the blank, said machine comprising pawl and ratchet means for turning the feed rolls including a movable pawlcarrier, spring means for retracting the pawl carrier to enable the pawl to engage a new tooth of the ratchet, a spring operated actuator lever normally engaging the pawl carrier and urging it forward thereby to turn the feed rolls, and means moving in timed relation to the barrel for swinging said actuator lever out of engagement with the pawl carrier as the barrel oscillates.

15. A tack machine of the type having an intermittently oscillating blank supporting barrel, feed rolls for advancing a blank along the barrel, cutting means, and stop means for limiting advance of the blank, said machine comprising pawl and ratchet means for turning the feed rolls including a movable pawl carrier, spring means for retracting the pawl carrier to enable the pawl to engage a new tooth of the ratchet, an actuator comprising members disposed upon opposite sides of the barrel respectively and adapted alternately to engage the pawl carrier, means causing that one of the actuator members which at any time engages the pawl carrier to urge the latter forward in ratchet driving direction, and means for withdrawing the actuator member's from operativeposition as the barrel oscillates.

16. A tack machine of the type having means for supporting a blank, r'eed rolls for advancing the blank, cutting means, and stop means for limiting advance of the blank, said machine comprising pawl and ratchet means for turning the feed rolls including a movable pawl carrier, spring means for retracting the pawl carrier to enable the pawl to engage a new tooth of the ratchet, an actuator normally urging the pawl carrier in the opposite direction, and means for intermittently separating the actuator from the pawl carrier, thereby permitting said spring means to retract the carrier.

17. A tack machine of the type having an intermittently oscillating blank supporting barrel, and feed rolls for advancing a blank along the barrel,the rolls moving bodily with the barrel, said machine comprising pawl and ratchet means for advancing the feed rolls, said pawl and ratchet means including a movable pawl carrier, an actuator lever comprising a pair of arms disposed respectively at opposite sides of the barrel and adapted alternately to engage the pawl carrier, spring means urging the actuator lever in such a direction as to cause that one of its arms which engages the pawl carrier to press against the latter, and cam actuated means for swinging said arms out of operative position as the barrel oscillates.

Signed by us at Boston, Massachusetts, this 18th day of October, 1927.

GEORGE E. BAKER. HERBERT B. BAKER. EDWARD C. BAKER.

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