US1757812A - Staple-driving machine - Google Patents

Description

May 6, 1930. F. PQLzl-:R 1,757,812

STAPLE DRIVING M'ACHINE Filed Aug. 3, 1927 Patented May 6, 193

UmTiazn STATES .PATENT er1-"lcs FRIDOLIN I-POLZER, OF NORWALK, CONNECTICUT, ASSIGNOR TO TEE EH. HOTCHKISS COMPANY, OF NORWALK, CONNECTICUT, A CORPORATION OF .CONNIEC'JJICU'Il.v

STABLE-DRIVING MACHINE Application filed August 3, 1927. Serial No. 210,301.

This invention relates to staple driving machines, and may be usedeither in the socalled tacker type of machine in which for eX- ample the staplesv are driven through a tag to attach it to a shipping box, or also-called st-apling machine in which the staples are driven through two or more `sheetsI of paper and clinched on the under side thereof to secure the sheets together by means of an lo` anvil usually mounted on a base pivoted to the housing or upper section of the machine. Y Vs shown in the drawing it is-illustrated as applied to a tacking machine although it will be understood the same mechanism may beused for a so-called stapling machine in which an anvil is used to cooperate with the plunger to clinch the staples.

This invention relates to the type of machine in which the staple driving plunger is v2`0'op`erated by means of a spring to drive the staple and the operator on each operation compresses thi's spring and then releases the lplunger-for the driving operation.

Tt is an object of the invention to provide a `construction of this type which is much more simple than that now generally applied, andl therefore, maynot only be manufactured and assembled at less cost but is much more re liable in operation as it is less liable to get out of order. l

Tt is also an object of the invention to pro vide an improved means for actuating` thel plunger to compress the spring, and release the plunger for the driving operation, and it is a still further object of the invention to provide improved cushioning means for the plunger. f

Another object is toprovide an improved feeding means for the staples.

With the foregoing and other objects in view, I have devised the construction illustrated in the accompanying drawing forming a part of this specification. In this drawlng, s v

Fig. 1 is a vertical longitudinal section through the device showing the elements in A the normal position of rest.'

Fig. 2 is a similar view showing the plunger partially retracted and the elements in the position they occupy a short time prior tothe release of the plunger for the staple driving operation.

Fig. 3 is a detail section substantially on line 3 3 of Fig. 2. Y ,Figa 4 is a detail elevation looking from the front with the plate section in front of the staple guideremoved, and

Fig. 5 is a detail plan View ofthe plunger operating4 ratchet.

vThe device comprises a housing 10 of any desired shape having a handle portion 11 for proper handling of the device. Mounted in al slot extending longitudinally in the lower portion of the housing is a supporting bar 12 for the staples 13 of substantially U-shape so that they straddle the top of this bar with the prongs in the vertical position and pointed downwardly. There 1s sufficient clearance along the sides of the bar at the upper portion thereof between the sides of the bar and the walls of the housing to give the proper clearance for the staples. The bar and walls of the'housibng thus form a suitable guide for the staples as they are fed` .verted U-shape'in cross section to straddle the bar 12 and engage at its forward end the `staples on this bar, and it is guided by the bar and the walls of the housing. The' side walls of the housing may overhang, as shown at 15, to engage the top of this follower 'r a block 16 mounted on the follower to'retain it in 'proper position on the bar.- A coiled springr 17 of fiat metal is mounted on a trans-V verse pin 18 to which one end is connected and its 'free end is connected to a handle stud 19 having a socket therein to receive a pin 20 carried by the follower. It is preferred-that this pin be inclined backwardly somewhat ns indicated, so that thev pull of the spiing will tend to retain the handle on the pin, but it'will be apparent= this handle may be easily lifted upwardly from the pink to release the follower and per- CIJ mit it to be removed by sliding it olf the rear end of the bar 12 so that a new supply of staples may be inserted from this end the guide.

At the front of the housing is a guideway 23 for a plunger 24 so that the plunger may reciprocate up and down across 'the front end of the bar 12. The lower portion 25 of this. plunger is reduced somewhat in thicl ness so as to provide a shoulder 26 and to make this portion 25 of. substantially the -thickness of the width of the staple, and

in one piece with it or made as a separate ele- A ment to which` the lower portion of the plunger is connected as by a vpin 29. This construction forms at the bottom of this guideway a shoulder 30 on which rests a helical spring 31 embracing the plunger which forms a cushion or buffer toarrest movements of the plunger should the device be operated when not held against work. It will be apparent that without this spring there will be a severe hammer on the housing` or mechanism'if.the`machine were so operated without the spring 3l. Above the` plunger block 28 is another helical spring 32 engaging the top of this plunger and preferably'seated within a 'recess'therein Atits upper end it seats within a recessed disc 33 which is mounted on the end of an adjusting screw 34. To retain this disc in proper re-` lation'to the screw the screw has a reduced end 35 seated in an opening-in the dise. lThe screw 34 is threaded in the top plate 36 which is detachably mounted on the housing and a removable front' plate 37 by means of the screws 38. By adjusting the screw 34a the tension of the spring 32 may be adjusted and then the screw may be locked in adjusted position by thel lock nut 39. It is preferred that the removable front plate 37 be made inftwo sections, the lower section 40 at the lower part of the machine in front of the guide bar 12 being removable independently of the upper section to give access to the forward part of the guideway for the staples and the guideway for the plunger should there be any clogging. y

The, plunger/is operated b v being lifted vertically and then released so that it is forced downwardly bythe spring 32.to drive the staples. At the rear of the plunger block 28 xs a rotatable ratchetV wheel 411mountedto turn on a transverse pin 42. This wheel has any desired number of teeth 43 in position so that as the wheel is rotated these teeth will successivelyengage the lower shoulder 44 of into i the plunger block 28, and therefore, lift the plunger against the action of the sprin 32 and compress this spring. This ratchet w eel is rotated with a step by step movement by means of a pawl 45 pivoted at 46 toa hand lever 47. This lever is pivoted in thehousing at 48, and the wheel 41 has a central groove 49 at the bottom of which are notches 50 of the same number as the number ofteeth on the wheel and arranged to receive the lower end of the pawl 45. This pawl is held against the bottom of the groove by means of a spring 5,1. The lever 47 is normally held in the upper position, as shown in Fig. 1, by means of a spring-52 seated at its lower end lin a recess 53 in the housing and at its upper end embracing a pin 54mounted on the lever 47. The toothed wheel 41 is so proportioned with respect to the movement of the lever 47 that if the free end of this lever is depressed or fprced downwardly as indicated, in Fig. 2, one of the teeth 43.0f the wheel will engage the under shoulder 44 of the plunger and will raise the plunger as the wheel is'turned tothe right or clockwise, as viewed in the ligure. The lever 47 has suiiicient movement so as to turn the wheel sutilciently to allow the tooth which has raised the plunger to slide off the shoulder 44 and ythus release the plunger. This permits the spring 32 which hasbeen compressed by the upwardmovement of the plunger to force the plunger downwardly to the position of Fig. 1 and drive the staple which was in the guideway beneath the lower end of the reduced portion'25 of the plunger.` rIt will be noted from Fig. 1 that this portion of the plunger is of suicient length to extend to the lower end of the guideway or that is to the bottom edge -of the bar 12 to insure that the staple is properly driven; The vhousing may also have a stop wall-,55 to be engagedby the shoulder 26 on the plunger to limit its downward movement.. As soon as the lever 47 is released it is again moved upwardly to the position of Fig. 1 bringing the free end of the pawl 45 into the neigt nptc'h 50 in the wheel, andthe 'machine is now ready to repeat the operation and drive another staple.

It will, of course, be obvious that as the staples are driven the remaining staples are fed forwardly on the bar 12 by spring 17 acting through the follower 14 bringing these staples successively into the proper driving position under the reduced portion '25 of the plunger. y. l It will be apparent that the device is extremely simple in construction, and therefore, may be manufactured and assembled at Vcomparatively low cost, and will be reliable in operation. The toothed ratchet .wheel 41 is of rugged construction'and has an extended bearing surface for each vset of teeth on the plunger block 28,-it being apparent from Fig. 5 that there' are really two sets of these teeth.

This element may be made of properly tempered steel so that it Will wear for ai long Y time, -and as the location of the Wheel automatically moves the teeth from engagement with the shoulder 44 on the plunger the operation of releasing the plunger is positive, so that .it will be sure to operate and will only operate at a given time or given position of the operating lever. The helical type of springs shown are the most reliable in operation as they have a longer life and are less liable to breakage. ,It is also easier to make springs of this type of a uniform quality.

Having thus set forth the nature of my invention, What I claim is:

1. In a staple driving machine, a housing,

a staple guide in the housing, a reciprocable plunger movable transversely of said guide for driving the staples, a spring for shifting the plunger to drive a staple, a rotatable Wheel having teeth arranged to engage a shoulder connected to the plunger to shift said plunger against the action of the spring, and means for rotating said Wheel with a step by step movement to alternately retract l the plunger and then release it to permit operation thereof by said spring.

2. In a staple driving machine, a reciprocable plunger for driving the individual staples and provided with a shoulder, means for feeding the staples to the driving position under the plunger, a spring for forcing the plunger forwardlyto drive a staple, a rotatable ratchet Wheel having teeth to successively engage said shoulder and retract the plunger against said spring, and means for rotating said Wheel with a step by step movement.

3. In a staple driving machine, a reciprocable plunger for driving the individual staples and provided with a shoulder, means for feeding the staples 'to the driving position under the plunger, a spring for forcing the plunger forwardly to drive a staple, a. rotatable ratchet Wheel having teeth to successively engage said shoulder and retract the plunger against said spring. a pivoted lever, a pawl carried b v the lever, and said Wheel having spaced shoulders cooperating with the pawl to rotate the wheel with a step by step movement as the lever is swung on its pivot.

4. In a staple driving machine, a reciprocable plunger for driving the individual staples and provided with a shoulder, means for feeding the staples to the driving position under the plunger, a spring for forcing the plunger forwardly to drive a staple, a spring embracing the plunger and forming a cushioning means for the plunger at the end of the driving operation, a rotatable ratchet wheel having teeth to successively engage said shoulder and retract the lplunger against said spring, a pivoted operating lever, and a one way driving connection from said lever to said Wheel.

5. In a staple driving machine, a reciprocable plunger for driving the individual staples and provided with al shoulder, means for feeding the staples to the driving position under the plunger, a spring for forcing the plunger forwardly to drive a staple, a rotatable ratchet wheel having teeth to succcssively engage said shoulder and retract the plunger against said spring, a pivotcd hand lever, a paWl pivoted to said lever, said wheel having shoulders to engage the end of the paWl whereby said wheel may be rotated with a step by step movement, a spring holding the pawl against the wheel, and a spring tending to hold the lever in the retracted position in preparation for the next staple driv` ing operation.

In testimony whereof I aiiX my signature.

FRIDOLIN POLZER.

SPO

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