US2315108A - Wire feeder for nail machines - Google Patents

Description

INVENTOR Charla-5R. Chism 2 Sheets-Sh eet 1 u llIl 13.

c. R. CHISM WIRE FEEDER FOR NAIL MACHINES F 1 d May 5 1942 March 30, 1943.

March 30, 1943. C c s 2,315,108

WIRE FEEDER FOR NAIL MACHINES Filed May 1942 2 Sheets-Sheet 2 4a .1 2g. 2. 30 1H 46 10 x L -4 if. I l 122 INVENTOR Charleslf, Chism W fimey.

, being positioned Patented Mar. 30, 1943 UNIT ED STATES PATENT OFFICE 2,315,102; i

wmE FEEDER FOB NAIL, MAcnmEs Charles a. 'Chism, Pittsburg, Calif. Application May 5, 1942, Serial No. 4413865 3 Claims. (01.

v This invention relates to improved means for feeding wire or rod stock to a nailmaking machine. More specificallythe present invention contemplates specific features of design and arrangement particularly described in the following specification, shown in the accompanying drawings and defined with particularity in the appended claims.

In the drawings:

7 Figure 1 is a perspective improved feeder;

Figure 2 is a plan view illustrating the feeder;

Figure 3 is a cross section on line III-1 11 of Figure 2;

Figure 4 is an enlarged detail of the gripping device of the present invention; and

Figure'5 is a view similar to Figure 4 illus devices used in the prior art nail making machines.

Referring in detail to the drawings, the apparatus includes a roller holder lIl having a slot I2 which extends inwardly The holder is pivotally mounted on a steel post I8 carried by a reciprocating feed table I8. This post passes freely through the hole It to provide for necessary clearance, marked C in Figure 3, to insure proper operation of the coacting parts. A particular novel feature of the invention resides in the provision of an anti-friction ball bearing roller 20 carried by a spindle 22 and having bearing balls 24 which make a rollingantifriction contact with the Spindle 22, the roller in the slot I2 and the spindle being rigidly secured to the holder III. The respective sizes of the roller and the holder are such that the periphery of the roller extends slightly beyond the outer portion of the holder. The ball bearing roller 20 bears firmly on the post I8 on the forward wire feeding stroke of the table, and during the back stroke the clearance C permits the holder to shift with respect to the post a to the post hole I4.

this action there is provided theholder I; Thus sufficient distance to release the pressure and thus free the rollergrip on the post. To ,insure a spring 28 which surrounds the post I8 and has one end anchored thereto at 30. The other end 32 of the spring is engaged with a stud 34 extendedoutwardly from the spring normally tends to turn the holder I0 counterclockwise, as viewed view of a portion of a nail rnaking'machine equipped with the improved an oscillating arm 38 forward stroke of the with the feed table in Figure 2.

The post I8: and holder move back and forth l8 which in turn slides in suitable fixed ways 31, the'table being actuated by having a forked end 40 which straddles a bolt 42 secured to the table and passing through a groove 44 of a wire guide member 46.

In normal operation, throughout both the forward and return strokes, the roller 20 'contacts the wire stock W to be fed, this contact being maintained by the spring-28 surrounding the post l8. The resulting pressureof the spring, coupled with the friction developed between the roller and the wire during travel, causes theroller and the holder II! to move toward the steel post as the table travels toward the nail dies conventionally indicated at 48. Since the radius of the roller is greater than the distance between the roller center and the post hole circumference, the roller contacts with the steel post. The resulting pressure at this point bind the roller to the steel post and prevent rotation of the roller. .Since the roller cannot rotate, it will tend to grip the wire. Thus upon the table IS the wire will be ad.- vaned toward the dies 48. Figures 3v and 4 show the parts in the feed position. During the return stroke the parts take the position of Figure 5, the friction-between the wire and the roller acting in the opposite direction. This will tend to twist the roller away from the steel post. Thus, because of the allowed clearance at the steel post hole, the roller is moved free of the post and is allowed to turn on its axis and thus 'roll along the wire as the feed table returns to its initial position.

It will be apparent that after eachfeeding stroke a slight turning movement is imparted to the roller. This results in periodically presenting a different wear surface of the roller to the wire at eachstroke of the machine. This is ad- ,vantageous because itadds greatly to the.life of the wire engaging part of the nail machine.

of contact is great enough to the wire stock in said guide different position each. time the wire'is engaged and the rolling contact prevents the marring or scratching oflthestock and thus overcomes an in herent defect in the conventional feeding device heretofore used.

Having thus described my invention, what 'I" claim is: v p

1. A feeder for wire stock comprising a feed table having a groovedl'guide for the wire stock, means for imparting forward and backward ing a post carried by the table, said holder having a bearing opening therein of larger diameter than the post to provide a clearance, a roller journaled in the holder and coacting vwith the post ,to grip upon forward'movestock forward; a spring tending to turn said 7 strokes to said table, a holder pivotally engagment of said table, a spring'tending to turn the holder about said post in a directiontoward the 7 wire stock and also effective upon the back stroke of thefeedtable to shift the holder with} relation to said post to an extent permitted by saidclearanceto thus free the grip of thefroller upon the post and thereby cause the, roller to'tlurn as it rides on the wire during the back stroke of the table.

v 2. A feeder for wire stock comprising a feed table having a grooved wire guide a pivot post 5 secured to the table, a holder having a bearing opening of larger diameter than the post to pro-- vide a clearance, a Wire engaging roller journaled, on a spindle carried by said holder and having bearing balls incorporated therein for anti frlction contact with said spindle, the periphery of,

said roller contactingboth the post and the wire stock in said guide upon theiorward movement of said table to thereby grip and move said wire roller about said post in a direction toward said wire stock and also effective upon the back stroke of the feed table to shift the holder with relation to said post to an extent permitted by said clearance to thus free the grip of the roller upon the post and thereby cause the roller to turn as it rides on the wire stock during said back stroke of the table.

3.In a nail making machine, a feeder for the awire nail stock comprising a feed table carrying a grooved guide, means for imparting forward and backward strokes to said table, a post secured to the table, a holder having a bearing opening therein for coaction with the post and of larger diameter than the post to provide a clearance, a ball bearing wire engaging roller carried by a spindle secured to said holder and coacting with said post 'to grip the wire stock in said guide upon the forward movement of said table, a torsion spring having one end engaged with the post and the other end connected to the'holde'r and tending to turn it about the post'inra direction toward said wire stock and also effective upon the back, .strokeof the feed table to shift the holder with relation to the post to an'extent permitted by said clearance to thus release the grip of the roller upon the post and thereby cause the roller to turn as it travels along the wire stock during the back stroke'of the table whereby upon subsequent strokes of thevfeed table different portions of the-periphery of the roller will successively come into gripping engagementwith the wire stock and thus distribute the wear and consequently lengthen the useful life of the roller.

HARLES R. CHISM.

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