US2621345A

US2621345A - Machine for making tacks

Info

Publication number: US2621345A
Application number: US139304A
Authority: US
Inventors: Robert V Howell
Original assignee: Tok Inc
Current assignee: Tok Inc
Priority date: 1950-01-18
Filing date: 1950-01-18
Publication date: 1952-12-16
Anticipated expiration: 1969-12-16

Description

Dec. 16, 1952 R. v. HOWELL 2,621,345

MACHINE FOR MAKING TACKS Filed Jan. 18, 1950 OWELL Snventor ROBERT V. H

Patented Dec. 16,1952

UNITED STATES MACHINE FOR MAKING TACK'S Robert V. Howell, Fort. Worth, Tex, assignor to Tok, Inc., Amarillo, Tex., a corporation of Texas.

Application January 18, 1950, Serial No. 139,304

August 12, 1947. This application relates in part a means and method for removing flash or excess material which may result from the forming operation referred to in. the foregoing object.

A further object of the invention is to provide, in a pair of roll dies for forming tacks, a

means whereby the heads of the tacks are prevented from being formed in a direction. away from the lengths of their respective. shanks.

These and other objects of the invention will become apparent from the following description and the accompanying drawings, wherein:

Figure l is a broken side elevation of a. ma-

chine for making tacks of the described class,

and embodying the features of th present in.- vention.

Figure 2 is an enlarged perspective view of the roll dies, and particularly showing the arrange- -ment of a backing ring, for preventing the heads of. the tacks from expanding outwardly with respectto the lengths of the tack shanks.

Figure 3 is a vertical sectional view of the roll dies where they contact each other, and showing the position of the. backing ring with respect thereto- Figure l is a broken planview of a length of round stock and showing the progressive forma: tion of the tacks made therefrom inaccordance with the present invention.

Figure 5 is an enlarged plan. view of the trim die illustrated in Figure l, and additionally showing a suggested means for cutting the length of formed tacks into short strips for use in a-magazine type tack hammer.

Figure 6 is a broken elevation of the cutting ,means illustrated in Figure 5.

The machine illustrated in Figure 1. includes a frame or bed 10 supported on legs I l. Upon the frame l8 there is a bearing support i3 which rotatably supports the shafts M and of a pair of roll dies [6 and i1, respectively; and which dies are arranged in contact with each other in a vertical position. The roll dies It and II are respectively provided with annular grooves I8 vertical support 32.

and 1:9 which accommodatev a backing: band'or ring 20.. As shown in Figure 1, the ring 20. is supported. by a, bracket 2! mounted on the hear-- ing support [3, and which bracket is bifurcated at its outer end where it rotatably supports a T011.- er 22 for engaging the inner periphery of the ring 20. Anadditional guide member 23; may be seecured. to the bearing support 1:3. and arranged for; slidably engaging the ring 29 in front. of

the roll dies. I6 and I1. Cavities 24 and 25', each defining: one-half; a tack, are formed in the cylindrical surfaces of the roll dies I6 and IL The head ends of the respective cavities 24 and 25 open intov each. other so as to form the strips to be described. As. particularly shown in Figure 3, the. head ends: of the cavities 24 and 25 are open toward one side of the ring 20, and whereby the. latter will maintain. a flat surface on the heads. 25 of. the tacks to be formed. The lengths of the cavities 24 and 25, asv will beseen, will form the tack. shanks 211; Although not-shown in the: drawings, the roll dies l6 and I"! are geared to each other; and are arranged so that the cavities 2.4 and 25 will coincide with each other.

Mounted on the frame ID, by means of a support 23,. there is a trim die 29 which is'arranged opposite and slightly higher than the roll-dies i6 and ii. The form of trim die illustrated in.- cludes an eccentric 36' on one end of a shaft 31 iournaled in a vertical support 32., A connecting rod 33' slidably engages the. eccentric 311 at one end thereof, and whereas the other end is pivotally connected with. a punch 34 which operates in a guide 35 secured to the face: of'th'e The end of. the punch 34 is shaped to remove the: flash 36; which may ex'- between the. tack shanks 2.1-

A. hitch. feed. 31 is. provided. between the trim die 29 and. the. roll dies 16. and IT and is-operated. by a cam 38 mounted onth'etrim die shaft 3|.

The cam: 33 is cylindrical in shape and is provided. with a" cam groove-.35 around its: outer surface. i A slide 4!! is transversely mounted in the die support 32 and.- has aflaterally projecting pin. A l for engaging the sides of the cam. groove 39. A1vertical"bracketl2 is from linear motion into angular motion; The

lower end of the vertical shaft 43" is similarly provided with an ann 46'- which is connected with a feed bar 4| by means of a link 48 Pivotally connected thereb-etween." The feed bar 41 is arranged for reciprocating movement on a horizontal support 49 formed by the upper end of the die support 28. The strip of tacks 50 discharged from the roll dies l6 and 11 are received on top of the horizontal support 49 and beneath the feed bar 41. As shown in Figure 5, the horizontal support 49 is provided with a shoulder 52 for guiding the feed bar 41. There is a pawl 53 pivotally mounted in an opening 54 in the feed bar 41 by means of a pivot pin 55, and which pawl is arranged to engage the shanks 21 of the strip of tacks 56 and feed the latter toward the punch 34 of the trim die 29. An elongated opening 56 is also formed through the feed bar 41 to accommodate the punch 34.

Beneath the frame Hi there is a motor 51 which drives a pulley 58 by means of a belt 59. The pulley 58 is mounted on. a shaft 60 journaled in a supporting member BI and secured to the frame 10. There is a sprocket (not shown) mounted on the shaft fiflwhich drives the sprocket 62 mounted on the trim die shaft 3| by means of a chain 63. One of the roll die supporting shafts I is also driven by the last referred to shaft 60 through a train of reduction gears 64, 65, 66 and B1. The first referred to gear 64 of the train is mounted on the drive shaft 60, whereas the intermediategears 65 and 66 are mounted on an intermediate shaft 68 journaled in a supporting member 69 mounted on the frame [0. The last gear 6! of the train is mounted on the roll die shaft 5.

The tack strip cutting mechanism illustrated in Figures 5 and 6 is optional and is not necessarily a part of the present invention. The cutting mechanism Ill shown is comprised of a bracket ll supported by the die support 32 and has a vertically disposed ratchet wheel 12 mounted thereon. The number of teeth .13 around the circumference of the wheel 12 cor,- respond in number with the number of tacks to be cut from the original strip of tacks 50. The wheel 12 is actuated by a rod 14 slidably positioned through the die support 32 and has a lateral projection for engaging the sides of the cam groove 39. The opposite end of the rod '14 is provided with a pawl 16 for engaging the rachet wheel teeth 73, The side of the wheel 12 includes a cam 18 having an abrupt fall 19 in its periphery. A locking pawl 80 is pivotally mounted on the upper end of the bracket 'H and is arranged to engage the teeth 13 so as to prevent counter rotation of the wheel A stub shaft Bl projects from one side of the bracket H and pivotally supports an L- shaped follower 82 which operatesin the manner of a bell crank; One end of the follower 82 is in the form of an abrupt turn 83 for coaction with the fall 19 of the ratchet wheel cam 18. A circular knife 84 is also mounted on the stub shaft BI and has radially directed blades 85 arranged to receive the strip of tacks 50 therebetween as the latter is discharged from the feed bar 41. One face of the circular knife 84 is provided with rachet teeth 86 which coact with a pawl 81 secured to the end of the L-shaped follower 82 opposite the abruptly turned end 83. It is to be understood that the last described pawl 81 and the follower 82 are spring loaded so as to make constant contact with the last described rachet teeth 86 and with the cam 81, respectively.

The strip of tacks 50 may be formed of bar or wire stock which is preferably supported on 4 a reel 88 rotatably mounted on a standard 89 secured to the frame Ill. As the stock is fed between the roll dies l6 and I1, the previously described tack heads 26 and tack shanks 21 are formed, and usually have a certain amount of flash 36 between the said shanks. The strip of tacks 5D is then fed to a position beneath the punch 34 by means of the reciprocating hitch feed 37. It will be noted that the action of the cylindrical cam 38 is such that the hitch feed pawl 53 has the same number of strokes as the punch 34. After the punch 34 has removed the excess flash 36 from between the tack shanks 21, the strip of tacks 50 is fed between adjacent blades 85 of the circular knife 84. By reason of the action of the described cutting mechanism 10, the strip of tacks 50 is cut into short lengths 9D and which fall into a box 9| supported on the frame Ill.

The described form of the invention is not restrictive, but may be made in many ways within the scope of the appended claims.

What is claimed is:

1. A machine forming strips of tacks joined along opposite sides of their heads and having their shanks projecting perpendicularly with respect to the length thereof, said machine comprising a pair of roll dies each having coinciding tack-shaped cavities around the cylindrical surfaces thereof for nearly completely forming said strips of tacks, a trim die including a reciprocating punch forming a part thereof, said die being arranged for receiving the strip of tacks discharged from said roll dies, and a hitch feed positioned between said roll dies and said trim die, and means synchronizing said hitch feed with said trim die whereby the punch of the latter operates between the shanks of the tacks for removing flash therefrom.

2. A machine for forming strips of tacks joined along opposite sides of their heads and having their shanks projecting perpendicularly with respect to the length thereof, said machine comprising a pair of roller dies each having tackshaped cavities around the cylindrical surfaces thereof, the cavities in one said die being arranged to match the cavities in the remaining said die, and wherein the said cavities in each said die are joined with each other along the head portions thereof, and means removing the flash formed between the shank portions of the resulting tack strips as they emerge from said dies.

3. In a machine for forming strips of tacks joined along opposite sides of their heads and having their shanks projecting perpendicularly with respect to the length thereof as defined in claim 2, the construction wherein said roller dies have annular grooves in the cylindrical surfaces thereof and joining said tack shaped cavities at the head ends thereof, and a backing ring received within said annular grooves.

ROBERT V. HOWELL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 405,733 Griscom June 25, 1889 1,228,198 Frauenheim May 29, 1917