US2931537A - Fastener inserting devices - Google Patents

Description

April 5, 1960 Filed Feb. 20, 1957 K. H. CARPENTER FASTENR INSERTING DEVICES 5 Sheets-Sheet l April 5, 1960 K. H. CARPENTER 2,931,537

FASTENER INSERTING DEVICES Filed Feb. 20. 1957 5 Sheets-Sheet 2 gli April 5, 1960 K. H. CARPENTER 2,931,537

FASTENER INSERTING DEVICES Filed Feb, 20, 1957 heets-fsheet 3 April 5, 1960 K. H. CARPENTER 2,931,537

FASTENER INSERTING DEVICES Filed Feb. 20, 1957 5 Sheets-Sheet 4 Inventor L'ZL H. @1r/belde?" April 5, 1960 K. H. CARPENTER 2,931,537

FASTENER INSERTING DEVICES Filed Feb. 20, 1957 5 Sheets-Sheet 5 flig- Y i? l 4Z 2/6 /34 me 06 50 III /z @L [n1/en tor i LHCar/benter FAsrENen nvsaarnso Daviess Keith H. Carpenter, Hamilton, Mass., assigner to United Shoe Machinery Corporation, Flemington, N. J., a corporation of New Jersey This invention relatesV to fastener inserting and more particularly to manually operated automaticffeed devices for inserting fasteners, such as nails, screws and tacks, etc. Many inserting devices of this' type 'comprise a portable driving tool connected to a remotely located feeding mechanism which automatically separates, orients and propels fasteners one at a time through a conduit to the tool upon receipt of-a signal emanating from the tool.

The more common pneumatic portable driving tools may be classified in two general categories, (l) those in which the actual fastener driving operation is substantially instantaneous, for example, a single-'blow nail or tack driver, Vand (2) those in which the driving operation requires a somewhat longer or sustained period of time, for example, multiple-blow nail drivers and rotary screw drivers. Feeding mechanisms used with a tool in the first category may deliver the next fastener'as; soon as the tool is fired since the tools driving period is sufficiently short so as to be completed before the next fastener can be propelled throughy the delivery conduit, thereby sub'- stantially eliminating the possibility of ajam caused by more than one fastenerbeing in the to`ol at thesame time. However, with tools of the second category having longer or sustained driving periods, the actual feeding of asubsequent fastener must be delayed until the driving operation ceases, otherwise a jam will occurk at the tool.

In United States Letters Patent No. 2,785,400, granted March 19, 1957, inthe names of Donald B. Mcllvin et al., there is Vdisclosed a feeding mechanism for supplying fasteners to portable tools ofboth categories. The present invention is an improvement on the type of device disclosed in the Mcllvin patent particularly when usedfor feeding fasteners to tools of the second category, i.e. tools that have sustained driving periods, such-as multiple-blow nail drivers and rotary screw drivers. With the prior art machine it is necessary to employ an air accumulator with a separate control valve when the-machine is used to feed fastenersto tools having sustained driving periods, the accumulator and valve not Vbeing required when feeding tools that drive fasteners substantially instantaneously. Obvious advantagesboth in economy and ease of manufacture result if the air accumulator and its separate valve mechanism can be eliminated from this machine while retaining its present efficient manner of operating.

Therefore, it is an object of this invention to provide an automatic feed mechanism of the type disclosedin the above-mentioned Mcllvin patent which does not require an air accumulator with a separate control valve in order to feed fasteners to driving toolshaving'` sustained driving periods.

AnotherV object of this invention is toprovide an` automatic feed mechanism of the type disclosed in the abovementioned Mcllvin patent which is .more economicalto construct and operate.

ln accordance with the various features of this invention there is provided an apparatus for. transferring headed fastenersand the: like comprising lanincli'ned raceway for le States 'Patent' ice heads uniformly oriented with respect to each other and a downwardly inclined sleeve rotatably mounted adjacent the lower end of the raceway to separate fasteners one at a time from the raceway and release them into a delivery conduit leading to a driving tool. A slot is formed in one side of the rotatable sleeve in order that a fastener will pass from the raceway into the sleeve when the slot faces the raceway and will be preventedy from doing so when the slot faces away therefrom.- The sleeve is at all times urged into a position wherein its slot faces away from the raceway by a compression spring acting through a rack and pinion. To rotate the sleeve so that its slot moves into fastener receiving position there is provided a iluid actuated` piston acting in a direction opposite to the spring but which imparts motion through the same rack and pinion. AThere are provided means for. retaining and releasing fasteners in the raceway actuated by a double acting liuid operated'piston whichis supplied with operatf ing fluid through a passageway in the form of a signal line leading'frorn the driving tool.

In addition to actuating the retaining and releasing means,the double; acting piston also operates to direct a llow of pressurized fluid into the sleeve and thro-ugh the delivery conduit to propel fasteners to the driving tool in timed sequence with the rotation of the sleeve.

Through the provision of` appropriate flow check valveY means interposed between the fluid passageway and the double acting piston, a controlled sequence of operation results between the action of. the retaining and releasing means, the rotation of; the sleeve and the driving tool whereby one fastener at a time is fed to the tool and only when the tool is in condition. to receive it, thereby eliminating the need lfor an air accumulator and aA separate con.- trol valve to delay the feeding of fasteners when they arefed to tools having sustained driving periods.

The` abovevand otherr features of the invention, including variousz novelV details of construction and combinations of4 parts, will now bemore particularly described with reference to the accompanying drawings and pointed ou inthe claims.

In the drawings,

Fig. l is a sidel elevation of a machine embodying the invention for alining fasteners with respect to their ends and for -transferring them one at a time under pres.- sure through a delivery conduit;

Fig. 2 is a side elevation, partly in section on a larger scale, ofz part of theA machine shown in Fig. l; v

Fig. 3 is a plan view, partly in section, of operating mechanism for separating a single fastener, transferring it-to a delivery conduit. andV propelling it therethrough un.- der pressure;

Fig. 4 is a side elevation, partly in section, of the mechanismshown in Fig. 3;

Fig. 5 is a .diagrammatical view of the pneumatic cir;- cuit of the machine shown in Fig. 1 as employed with a rotary screw driver having a sustained driving period;

Fig. 6 is a view similar to Fig. 3 of an alternative form of a mach-ine embodying the invention;

Fig. 7 is a side elevation, partly in section, of the mechanism shown in Fig. 6; and

FigjS is a diagrammatical view ofthe pneumatic circuit of the alternative form of the machine shown in Figs. 6 and 7.

The general organization of a fastener feeding machine embodying the invention is shown in Fig. l. A hopper 10 for holding a supply of randomly oriented fasteners, such as nails or screws, is secured to a main frame l2 which may beVV mounted on a bench or other suitable support. Forming one side of the hopper is an elevating mechanism for lifting. fasteners from the hopper andclelivering ythem to a downwardly inclined, slotted raceway 1 4 al011Z.-,-which. the. fasteners slide ina uniformly alined relationship, suspended by their heads. The hopper, elevating mechanism and raceway are identical with those disclosed in United States Letters Patent No. 2,819,465, granted January 14, 1958 in the name ofDonald B. Mc- Ilvin, and are herein described only briey. The elevating mechanism comprises a plurality of lift slides 16 connected by means of a piston rod 18 to an air motor 20 which is controlled by a valve 22 for reciprocating the slides. Associated with the raceway 14, which is adjustable widthwise to accommodate various types and'sizes of fasteners, is a rotary reiector 24 to expel any inisalined Vfasteners from the raceway. The rejector is journaled in the frame 12 and is operated by means of a continuous flexible belt 26 passing around a pulley 28 and drive'n by a pawl clutch 30 which is operativelyV connected by means of a bracket 32 to the lift slides. Secured to the frame 12 and mounted at the lower end of the downwardly inclined raceway 14 is a separating and feeding mechanism 34 which separates the endmost fastener from those in the raceway and delivers it under pressure through a delivery tube 3S to a driving tool, such as a pneumatic nail or screw driving gun T (Figs. and 8), in response to a signal from the driving tool. The separating and feeding mechanism 34 is pneumatically operated, being connected to the same source of pressurized air as are the driving tool and the motor 20 which operates the lift slides 16 and the rotary rejector 24.

Referring to Fig. 4, the separating and feeding mechanism includes fastener retaining and releasing means in the form of a presser foot 36 of rubber or similar material which is arranged to be moved toward and away from the lower end of the raceway 14 to engage and release the heads of fasteners, herein illustrated as screws, as they slide down the raceway. The presser foot 36- is secured to a double acting piston 38 which reciprocates within a two-diameter cylinder 40 mounted on a bracket 42 which is adjustably secured to the frame 12 by screws 44 passing through slots 46 in the bracket. The twodiameter cylinder 40 comprises an upper cylindrical chamber 48 and a lower cylindrical chamber 50 of somewhat larger diameter than the chamber 48. The piston 3S has formed on its upper end a piston head 52 and somewhat therebelow a second head 54 of the same diameter. Separating the heads 52 and 54 is a necked area 56. The lower end of the piston 38, to which the presser foot 36 is attached, is formed as a cylindrical portion 58 of slightly greater diameter than the necked portion 56 but of smaller diameter than the heads 52 and 54. An O ring 59 is fitted in the lower end of the cylinder 40 to form an airtight seal with the cylindrical portion 58. An air inlet titting 60 is threaded in the lower portion of the cylinder 40 and communicates with the larger diameter chamber 50. Another fitting 61 is threaded in the cylinder 40 above the fitting 60 and communicates with the smaller diameter chamber 48. Still another fitting 62 is threaded in a cap 63 which forms a closure on the upper end of the cylinder 40, the fitting communicating with the smaller diameter chamber 48 above the piston head 52. The presser foot 36 is normally held upwardly away from the raceway 14 by compressed air entering the larger diameter chamber 50 through the fitting 60 and acting against the lower face of the piston head 54. The effective area on which the air within the chamber 50 acts is the area of the head 54 minus the area of the cylindrical portion 5S.

As seen in Figs. 2 and 4, the lower end of the raceway is sloped along a portion 64 substantially parallel to the bottom of the presser foot 36. The sloped portion 64 terminates abruptly exposing a shoulder or receiving area 66 extending beyond the presser foot and spaced slightly below the portion 64. The receiving area 66 forms an acute angle with the axis of the piston 38. In its lower position, 'as-seen in Fig. 2, the presser fo'ot engages the heads of fasteners, herein illustrated as screws,-spaced along the portion 64, and when the presser foot is in its normal or elevated position (Fig. 4) the endmost screw will fall onto the receiving area 66, the remaining screws each moving downwardly along the sloping raceway to take the position of the one just preceding. Only one screw at a time is permitted to fall onto the receiving area 66 by means now to be described.

Adjacent the receiving area 66 is located a sleeve 68 rotatably mounted in a housing 70 secured to the frame 12 by a screw 73 threaded in the frame 12 and passing through an ear formed on the housing 70. On the lower end of the sleeve 68 is a pair of anges 78 with an annular recess formed therebetween. A projection 82 on the end of a screw 84 threaded in the housing 70 loosely enters the recess 80 permitting the sleeve to rotate while preventing axial movement relative to the housing. The end of the flexible delivery conduit 35 for conducting fasteners to the inserting tool is held adjacent the lower end of the sleeve 68 by a titting 86 removably secured within the housing 70 by a spring-biased detent 8S or equivalent means. A pinion is located on the upper end of the sleeve 68 and in one side of the sleeve between the pinion and the anges 78 is formed an axially extending slot 92. In its normal or first position the closed wall of the sleeve faces the receiving area 66 (Figs. 3 and 4) the sleeve being rotatable to a second position wherein the slot 92 then faces the receiving area (Fig. 2). As seen in Fig. 4, which shows the presser foot and the sleeve in their normal positions, the presser foot being elevated and the closed wall of the sleeve facing the receiving area, the head of a screw is on the receiving area 66, its pointed or shank end bearing against the sleeve since the receiving area is angularly disposed relative to the axis of the sleeve as well as to the axis of the presser foot 38, these axes being substantially parallel. The spacing of the raceway relative to the sleeve determines the size of the receiving area 66 permitting the head of the screw to be accurately positioned thereon, the raceway being adjustable toward and away from the sleeve by means of screws 74 passing into the frame 12 through slots 76 in the raceway. The shank of the next screw in line on the slope 64 is in contact with the periphery of the head of the screw on the receiving area (Fig. 4). Thus it is impossible for the next screw in line to move onto the receiving area until the first screw has been removed.

When the sleeve 68 is rotated to the second position wherein the slot 92 faces the receiving area, the presser foot 36 will already have been moved downwardly, in 'a manner hereinafter to be explained, and will have contacted the screws on the sloped portion 64. At this time the screw on the receiving area drops off into the sleeve', falling into the conduit 35, ready to be conveyed therethrough to the inserting gun. The remaining screws remain motionless on the slope 64 of the raceway until the presser foot is again moved upwardly. It is within the scope of this invention to construct the apparatus with the slope 64 continued downwardly to a point where it is almost in contact with the sleeve 68 whereby the stepped receiving area 66 would be eliminated. The device would operate in the same manner except that the lower portion of the endmost screw released by the presser foot may be out of engagement with the wall of the sleeve.

The means for rotating the sleeve will now be described. Engaging the pinion 90 (Fig. 3) is a rack 94 ixed to a rod 96 of a piston 98. On the end of the piston is a head 102 having the largest diameter of any portion of the piston. The'piston 98 is slidable within 'a cylinder 104 which forms the upper portion of the fitting isthreaded 'in the cap 108 to conducthigh pressure air into the cylinder 104. On the lower'end pressure.

tassa-,eer

fof the piston, as seen in Fig. 3, therefis formed a second Piston head 112, and separating the head 1--12 from the -middle portion of the piston is a necked area 114. An O ring on the head 112 assures an airtight fit between the piston and a sleeve 118 fitted within the cylinder 104, A cap 12d forms the lower end of the sleeve 118 and closes the end of the cylinder. Compressed between the cap and the piston head 112 is a spring 121. Threaded in the cylinder 184 is an air inlet fitting 124 and opposite the fitting 124 is threaded a second fitting 125, both fittings communicating with the interior of the sleeve 118. Still another fitting 126 is threaded in the housing 70 whereby air may pass into the sleeve 68v when the slot 92 in the sleeve is in alinement with the fitting.H

Referring to Fig. 5, whichis a schematic showing of the macliines pneumatic circuit, the fitting ;124 in the cylinder d is connected to the fitting 61 in the .presser foot cylinder 4i) by means of an airtight conduit 136. The fitting 125 which is located opposite the fitting 124 in the cylinder 164 is connected to the fitting 126 inthe housing 70 by an airtight conduit 132. interposed` in the conduit 132 is an adjustable fiow valve 133. The fitting 69 in the presser foot cylinder 49 is connected by an airtight conduit 134 to a pressurized line 136 leading from a source of compressed air. The fitting 110 in the cap 188 is connected by a line 137 to a signal line 1138 leading from the driving tool T. Also connected to the signal line 138 is a line 142 leading to the lfitting 62 in the presser foot cylinder 48. interposed in the line 137 is a conventional one-way restricted fiow checkI valve 144, vpermitting a relatively unrestricted or free fiow out of the fitting 110 but which restricts fiow through the line 137 into the fitting 110. interposed in the line 142 is a second one-way restricted fiow check valve 146 permitting free fiow through the line 142 into thefitting 62 but restricting the fiow out of the fitting .62. It will be noted that the amount of fiow through both of the oneway check valves is manually adjustable in a conventional A full cycle operation of the feeder-separator in supplying fasteners to a tool having a sustained driving period such as a multiple blow nail driver or a rotary screw driver, will now be described with reference to Fig. 5.

The tool T is shown as a pneumatic rotary screw driving .gun 180 of a well-known commercial type, not shown in detail, in which a screw S is rotatably driven by an air motor operated by actuating a trigger 1,82. The gun is 'connected by a line184 to the line 136 leading to the source of compressed air. The signal line 138 -is connested, Within the gun. to the line 184 so as to become pressurized when the gun is operated by the trigger 182 which opens a cut-ofi" valve 186 in the line 184.

Just prior to the time the gun is -triggered one screw is in the jaw of the gun having been either .placed there manually or delivered during the preceding cycle. Another screw is on the receiving area 66 withits shank or pointed end in contact with the closed wall of the sleeve 68, the slot 92 in the sleeve 68 facing away from the receiving area. The presser foot 36 is elevated out of contact with the screws on the sloped portion 64 of the raceway 14. The presser foot is held in elevated .position by pressurized air within the chamber 50 acting on the lower face of the piston head 54, the air within the lines 142, 137 and 138 then being at atmospheric When the signal line 138 becomes pressurized upon triggering the gun, compressed air enters the - lines 142 and 137 and from the line 142 passes freely -through the one-way restricted fiow valve 146 into the upper end of the chamber 41E-in the cylinder 40. Since Vthe area 'of ther piston head 5.1. is substantially greater than the area of the piston head 54 acted on by ythe line pressure air in chamber 50 the pressure foot will bedepressed, engaging the screws then on the slopedarea 64 of the 4raceway, by a .pressure which lis somewhat-less than-line, pressure. Y

terior of the tool.

The pressurized air from the signalline which enters Ithe line 137 is restricted in itsy fiow therethrough .by the one-way restricted flow valve 14d, entering' the cylinder v104 more slowly than the air which enters the cyl inder dit through the line 142 and does not-build up sufcient force to move the piston 98 until after the presser foot has descended. Accordingly, the sleeve 63 is not rotated until the presser foot has contacted the screws then on the sloped portion 64 of the raceway. During the short interval of time after the presser foot has descended and'before the rack 9d has rotated the sleeve, air is free to pass from the chamber 50 inthe presser foot cylinder 40 past the necked area 56 of the presser foot piston through the fitting 61, the line 130, the fitting 124 and past the necked area 114 of the piston 93 and into the sleeve 63 via the line 132. ThisV short blast of air is dissipated to atmosphere through the delivery conduit 35 and the interior of the gun 180. Since there is no fastener within the delivery conduit 35 this air blast in no way affects the operation of the gun or the transfer of a fastener.

After a short delay, sufficient pressurized air passes through the restricted fiow valve 144 into the top of the cylinder 1114 to move the piston 98 causing the rack 94 to rotate the sleeve 68, the slot 92 turning toward the receiving area 66 and the closed wall of the sleeve obstructing the further passage of air through the fitting 126. With the movement of the piston 98, the spring 121 is compressed and the necked area 114 of the piston moves out of alinement with the fittings 124 and 125 in the cylinder 164 thereby also prohibiting the further fiow of air through the line 130 intoY the line 132. When the sleeve 68 has been rotated 180, its slot 92 faces thereceiving area 66 and the screw resting thereon falls into the sleeve often coming to rest at a bend in the delivery conduit 3S ready to be blown to the driving tool. All of the foregoing takes place while the trigger of the driving tool is depressed and a screw is being inserted, consequently no delay in operation of the machine results. in addition to the elimination of the air accumulator and separate control valve another advantage of the present invention over the prior art is that the rack 94 and its operating piston 98, the sleeve 68 etc., are moved more slowly than heretofore, resulting in less wear and thus a longer useful life of these parts. The slower movement is obtained by the use of the compression spring 121 which at all times opposes the motion caused by compressed air acting on the piston head 102 and acts as a shock absorber particularly at the beginning and end of the movement of the rack 94 and piston 98.

Upon releasing the trigger 182 after the screw S has been driven, the signal line 133 becomes depressurized, the air therein passing to atmosphere through the in- Tlie spring 121 returns the piston98 and the rack. 94 to their initial positions, the air above the piston head 102 passing freely through the restricted fiow valve 144 into the signal line 138 and to atmosphere through the gun. At this time the necked area 114 of the piston 98 again becomes alined with the fittings 124 and in the cylinder 18d. The presser foot 36 has not, however, returned to its upper position since the one-way restricted fiow valve 146 prevents the rapid escape of air from above the piston head 52. Therefore, the pressurized air Within the. larger chamber 50 of the presser foot cylinder 40 is free to fiow past the necked area 56 of the piston 38 into the line 130, past the necked area 11d of the piston 98 through the line v132 and into the sleeve 68 through the slot 92 which then `controlled by .regulating the adjustable -flow valve .132- in .the .line 132.

It will be noted that substantially the same end result is obtained with a machine made in accordance with the present invention in feeding fasteners to a driving tool having a sustained driving period as is obtained with the prior art machine but without the need for an air accumulator and four-way control valve, to wit, the depression of the driving tool trigger actuates the separating and feeding mechanism to release a fastener into the delivery conduit and the release of the trigger causes the feeding mechanism to blow the fastener through the delivery conduit to the driving tool.

An alternative form of the machine made in accordance with the invention will now be described with reference to Figs. 6, 7 and 8. The slotted sleeve 68, its actuating rack 94 and the operating mechanism associated therewith are identical with those shown in Figs. 3 and 4 as are the raceway 14, its sloped portion 64 and the receiving area 66. The fastener retaining and releasing means, herein illustrated as the presser foot 36, is secured to the lower end of a plunger 190 slidably mounted within a piston 192. The piston 192 reciprocates within a two diameter cylinder 194 mounted on a bracket 196 which is adjustably secured to the frame 12 by screws 198 passing through slots 200 in the bracket. The two diameter cylinder 194 comprises an upper cylindrical chamber 202 and a lower cylindrical chamber 204 of somewhat larger diameter than the chamber 202. The piston 192 has formed on its upper end a piston head 206 and somewhat therebelow a second head 208 of the same diameter. Separating the heads 206 and 20S is a necked portion 210. The lower end of the piston 192 has formed thereon a cylindrical portion 212 of slightly greater diameter than the necked portion 210 but of smdler diameter than the heads 206 and 208. An O ring 214 is fitted in the lower end of the cylinder 194 to form an airtight seal with the cylindrical portion 212.

The plunger 190 to which the presser foot 36 is secured is slidable relatively to the piston 192 and has formed on its upper end a head 216 normally fitting within a counterbore in the piston head 206 and engaging a shoulder or seat 218 forming the bottom of the counter-bore. A spring 220 is compressed between the presser foot 36 and a recess 222 in the lower end of the piston 192 causing the head 216 normally to be seated against the shoulder 218. A necked area 224 is formed near the lower end of the plunger 190 and extending from the necked area 224 to the head 216 are a plurality of flats 226. The portion of the plunger 190 between the necked area 224 and the presser foot 36 fits loosely within the cylindrical portion 212 of the piston 192, thereby creating an air passageway between the necked area 224 and atmosphere.

An air inlet fitting 228 is threaded in the lower portion of the' cylinder 194 communicating with the larger diameter chamber 204. Another fitting 230 is threaded in the cylinder 194 above the fitting 223 and communicates with the smaller diameter chamber 202. Still another fitting 232 is threaded in a cap 234 which forms a closure on the upper end of the cylinder 194 and communicates with the smaller diameter chamber 202 above the piston head 206. Another fitting 236 is threaded in the cylindrical portion 212 of the piston 192 the lower part of which extends out of the cylinder 194. The fitting 236 moves with the piston 192.

The presser foot 36 is normally held upwardly away from the raceway 14 by compressed air entering the larger diameter chamber 204 through the fitting 228 and acting against the lower face of the piston head 208. The effective area on which the air within the chamber 204 acts is the area of the head 208 minus the area of the cylindrical portion 212.

Referring to Fig. 8, the fitting 124 in the cylinder 104 is connected to the fitting 230 in the presser foot cylinder .194V by an airtight conduit 240. The fitting 228 in the .presser foot cylinder 194 is connected by an airtight conduit 242 to the line 136 leading from the source of compressed air. The'tting 110 in the cap 108 is connected by a line 244 to the fitting 236 in the lower end of the presser foot piston 192. The signal line 138 leading from the driving tool T is connected to the fitting 232 cornmunicating with the upper end of the presser foot cylinder 194. Interposed in the line 138, near the fitting 232, is a conventional one-way restricted ow check valve 246 permitting relatively unrestricted or free ow from the line 138 into the fitting 232 but restricting or retarding the flow out of the fitting 232.

The operation of the above-described alternative form of machine embodying the invention will now be described with reference to Figs. 6, 7 and 8. Just prior to the time thc-gun is triggered one screw is in the jaw of the gun having been either placed there manually or delivered during the preceding cycle. Another screw is on the receiving area 66 with its shank or pointed end in contact with the closed wall of the sleeve 68, the slot 92 in the sleeve 68 facing away from the receiving area. The presser foot 36 is elevated out of contact with the screws on the sloped portion 64 of the raceway 14. The presser foot 36 is held in elevated position by pressurized air within the chamber 204 acting on the lower face of the piston head 208, the air within the signal line 138 then being at atmospheric pressure. When the signal line 138 becomes pressurized upon triggering the gun, compressed air passes through the one-way restricted ow valve 246 into the upper end of the chamber 202. Since the area of the piston head 206 plus the area of the plunger head 216, which in effect form substantially one continuous surface as shown in Fig. 7, is substantially greater than the area of the piston head 208 acted on by the line pressure air in chamber 204 the presser foot will be depressed, engaging the screws then on the sloped area 64 of the raceway, by a pressure which is somewhat less-than line pressure. Upon contacting the screws, the presser foot 36, and hence the plunger 190, come to rest. However, the piston 192 continues downwardly against the force of the spring 220 whereupon the plunger head 216 becomes unseated from the shoulder or seat 218, permitting the compressed air in the chamber 202 above the piston head 206 to by-pass the plunger head 216 and flow downwardly along the flats 226 to the necked area 224 of the plunger which is alined with the fitting 236. A portion of the air reaching the necked area 224 leaks to atmosphere past the lower end of the plunger 190. However, most of the air flows through the fitting 236, the line 244, the fitting 110 and into the cylinder 104 to rotate the slotted sleeve 68 releasing the screw on the receiving area 66 into the delivery conduit 35 in the manner described above. It will be noted that the sleeve 68 cannot be rotated to open position until the presser foot has engaged the heads of the fasteners on the raceway, assuring thereby that only one screw, i.e. the one resting on the receiving area 66, will be permitted to fall through the slot 92 in the sleeve.

Upon releasing the trigger of the driving tool after the screw S has been driven, the signal line 138 becomes depressurized between the tool T and the valve 246, the air therein passing to atmosphere through the interior of the tool. The presser foot cylinder 192 does not, however, return to its upper position immediately since the one-way restricted flow valve 246 permits only a slow escape of air from above the head 206. However, with the source of compressed air in the line 138 no longer available and with a slight drop in pressure above the piston head 206 the spring 121 which exerts a relatively high force on the piston 9S forces the air above the piston head 182 through the line 244, the fitting 236, the necked area 224 and to atmosphere past the loosely fitting lower 'end of the plunger 190. Upon the eventual return of the piston 98 to its initial position, but before the presser foot becomes elevated, the necked area 114 of the piston 98 is again alined with fittings 124 and 125 in the cylinder 104 and the pressurized air within the large chamfber 204 of the--presserfoot cylinder 2-,1194 is ffree to flow vpast the'necked area 210 of the piston 192,--into theli-ne 2413i?, past the necked area 1-14, of the piston 98, through the line 3132 and into the sleeve 68 through the slot 92 which then faces the fitting 126. This blast of air propels the screw, which dropped into the delivery conduit 35 when the previous screw is being driven, rapidly through said delivery conduit to the driving tool.

During tl e foregoing, when sufficient air from above the head 2% of the presser foot piston 192 passed through the check valve 246 to reduce the force holding the piston downwardly to an amount less than the force exerted oy the spring 220, `the piston 192 moved upwardly a slightV amount until the shoulder 218 on the piston head 236 again came into contact with the head 216 of the plunger 190. Subsequently, suiiicient air .passes through the valve 246 to allow the piston 196 and the plunger it? to reach their upper position as seen in Pigs. 7 and 8. Thereupon, the air passing from the line 242 into the line 24d is cut off by the piston head 208 and the apparatus is ready to repeat its cycle.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

l. -in an apparatus for transferring headed fasteners and the like, an inclined raceway for slidably supporting a plurality of fasteners with their heads uniformly oriented with respect to each other, a downwardly inclined sleeve rotatably mounted adjacent the lower end of said raceway, a delivery conduit communicating withV -thelowcr end of said sleeve, a slot formed in said =sleeve whereby a fastener sliding down said raceway will fall into the sleeve when the slot faces the raceway and will be prevented from doing so when the slot faces away from the raceway, fiuid operated actuating means for rotating said sleeve in one direction, resilient means at all times opposing the actuating means and operable to rotate said sleeve in the opposite direction, and uid operated means for retaining 'fasteners in -said raceway and operable to release one fastener at a time therefrom in timed sequence with the operation of said fluid operated actuating means said resilient means serving to absorb the shock of the rotation imparted to the sleeve by the uid operated actuating means.

2. In an apparatus for transferring headed fasteners `andthe like, an inclined raceway for slidably supporting -a plurality of fasteners with their heads uniformly oriented with respect to each other, a downwardly inclined sleeve rotatably mounted adjacent the lower end of said raceway, a delivery conduit communicating with the lower end of said sleeve, a slot formed in said sleeve whereby a fastener sliding down said raceway will fall into the sleeve when the slot faces the raceway and will be prevented from doing Yso when the slot faces away from the raceway, means for rotating said sleeve alternately in opposite directions, means for retaining Vfasteners inYsaid-raceway and operable to release one fastener at a time therefrom, 4and fluid valve means operated by the retaining and releasing means for directing uid flow into said sleeve and through said delivery conduit to propel a fastener therethrough only when said retaining and releasing means is in position to retain fasteners in the raceway.

3. In an apparatus for transferring headed fasteners and the like, an inclined raceway vfor slidably support- Ving a plurality-of fasteners with their heads uniformly oriented with respect to each other, a downwardly inclined sleeve rotatablymounted adjacent the lower end of said raceway, -a delivery conduit communicating with the lower end of said sleeve, -a slot formed in said sleeve whereby a fastener sliding down said raceway will fall into the sleeve when the slot faces the raceway and will be prevented from doing so when the slot faces away from the raceway, means for rotating said sleeve, a fastener engaging member, fluid pressure means for il@ rnoving said engaging member into and l"outa of engagement with fasteners in the raceway, `and uid valve Vmeans `within vthe 'iiuid pressure means for directing operating Afluid to said rotating means.

4. In an apparatus for transferring headed fasteners and the like, 'an inclined raceway for slidably supporting a plurality of fasteners with their heads uniformly oriented with respect to each other, a downwardly inclined sleeve rotatably mounted adjacent the lower -end of said raceway, a delivery conduit communicating with the lower end of said sleeve, a slot formed in said sleeve Vwhereby a fastenerl sliding down said raceway will fall into the sleeve when the slot faces the raceway and will be prevented from doing so when the slot faces away from the raceway, means normally maintaining v,Said sleeve in a position wherein its slot faces away from said raceway, first fluid operated means opposed to said sleeve .maintaining means and operable to rotate said vsleeve'to a position wherein its slot faces said raceway, movable means for retaining fasteners in and for releasing fasteners from said raceway, second fluid operated means normally maintaining said retaining and releasing means in a position to release fasteners from said raceway and operable to move said retaining and releasing means to a position wherein it retains fasteners in said raceway, a fluid passageway Yfor directing flow of pressurized operating fluid from an external source into and out of both said first and said second operating means, and means restricting the rate of fiow of operating fluid from said passageway into said first operating means to an amount less than the rate flowing into said second operating means.

5. In an apparatus for transferring headed fasteners and the like, an inclined raceway for slidably supporting a plurality of fasteners with their heads uniformly oriented with respect to each other, a downwardly inclined sleeve rotatably mounted adjacent the lower end of said raceway,A a delivery conduit communicating with the lower end of said sleeve, a slot formed in said sleeve whereby a fastener sliding down said raceway will fall into the sleeve when the slot faces the raceway and will 'be prevented from doing so when the slot faces away from the raceway, means normally maintaining said sleeve in a position wherein its slot faces away from said raceway, first fluid operated means opposed to said sleeve maintaining means and operable to rotate said sleeve to a position wherein its slot faces said raceway, movable means for retaining fasteners in and for releasing fasteners from said raceway, second fluid operated means normally maintaining said retaining and releasing means in a position to release fasteners from said raceway and operable to' move said retaining and releasing means 'to a position wherein it retains fasteners in said raceway, a fiuid passageway for directing How of pressurized operating fluid from an external source into and out of both said first and said second operating means, and means restricting the rate of How of operating fluid o'ut of said second operating means to an amount less than the rate flowing out of said first operating means.

6. In an apparatus for transferring headed fasteners and the like, an inclined raceway for slidably supporting a plurality of fasteners'with their heads uniformly oriented with respect to each other, a downwardly inclined sleeve rotatably mounted adjacent the lower end of said raceway, a vdelivery conduit communicating with the lower end of said sleeve, a slot formed in said sleeve Vwhereby a fastener sliding down said raceway will fall into the sleeve when the slot faces the raceway and will ybe prevented from doing `so when the slot faces away from the raceway, means no'rrnally maintaining said sleeve in a position wherein its slot faces away from said raceway, first uid operated means opposed to said sleeve maintaining means and operable to rotate said sleeve to a position wherein its slot faces said raceway, movable means for retaining fasteners in and for releasi-4 ing fasteners from said raceway, second fluid operated `means normally maintaining said retaining and releasing means in a position to release fasteners from said raceway and operable to move said retaining and releasing means to a position wherein it retains fasteners in said raceway, a fluid passageway for directing flow of pressurized operating fluid from an external source into and out o'f both said first and said second operating means, and a check valve interposed between said first operating means and said fluid passageway for retarding the flow of fluid into said first operating means.

7. In an apparatus for transferring headed fasteners and the like, an inclined raceway for slidably supporting a plurality of fasteners with their heads uniformly oriented with respect to each other, a downwardly inclined sleeve rotatably mounted adjacent the lo'wer end of said raceway, a delivery conduit communicating with the lower end of said sleeve, a slot formed in said sleeve whereby a. fastener sliding down said raceway will fall into the sleeve when the slot faces the raceway and will be prevented from doing so when the slot faces away from the raceway, means normally maintaining said sleeve in a position wherein its slot faces away from said raceway, first fluid operated means opposed to said sleeve maintaining means and operable to rotate said sleeve to a position wherein its slot faces said raceway, movable means for retaining fasteners in and for releasing fasteners from said raceway, second fluid operated means normally maintaining said retaining and releasing means Yin a position to release fasteners from said raceway and operable to move said retaining and releasing means to a position wherein it retains fasteners in said raceway, a

fluid passageway for directing flow of pressurized oper- ,and said fluid passageway for retarding the flow of fluid out of said second operating means.

8. In an apparatus for transferring headed fasteners and the like, an inclined raceway for slidably supporting a plurality of fasteners with their heads uniformly oriented with respect to each other, a downwardly inclined sleeve rotatably mounted adjacent the lower end of said raceway, a delivery conduit communicating with the lower end of said sleeve, a slot formed in said sleeve whereby a fastener sliding down said raceway will fall into the sleeve when the slo't faces the raceway and will be prevented from doing so when the slot faces away from the raceway, means normally maintaining said .sleeve in a position wherein its slot faces away from said raceway, first fluid operated means opposed to said sleeve maintaining means and operable to rotate said sleeve to a po'sition wherein its slot faces said raceway, movable means for retaining fasteners in and for releasing fasteners from said raceway, second fluid operated means normally maintaining said retaining and releasing means in a position to release fasteners from said raceway and operable to move said retaining and releasing means to a position wherein it retains fasteners in said raceway, a first fluid passageway for directing a flow of pressurized operating fluid from an external source into and out of said second operating means, and a second fluid passageway for directing a flow of pressurized operating fluid from said second operating means to said first operating means only when said retaining and releasing means is in position to retain fasteners in said raceway.

9. In an apparatus for transferring headed fasteners andthe like, an inclined raceway for slidably supporting a plurality of fasteners with their heads uniformly oriented with respect to each other, a downwardly inclined sleeve rotatably mounted adjacent the lower end of said raceway, a delivery conduit communicating with the lower end of said sleeve, a slot formed in said sleeve whereby a faster sliding down said raceway will fall into the sleeve when the slot faces the raceway and will be prevented frorn doing so when the slot faces away from the raceway, means normally maintaining said sleeve in a position wherein its slot faces away from said raceway, first fluid operated means opposed to said sleeve maintaining means and operable to rotate said sleeve to a position wherein its slot faces said raceway, movable means for retaining fasteners in and for releasing fasteners from said raceway, second fluid operated means normally maintaining said retaining and releasing means in' a position to release fasteners from said raceway and operable to move said retaining and releasing means to a position wherein it retains fasteners in said raceway, a first fluid passageway for directing a flow of pressurized operating fluid from an external source into and out of said second operating means, a second fluid passageway for directing a flow of pressurized operating fluid from said second operating means to said first operating means only when said retaining and releasing means is in position to retain fasteners in said raceway, and means restricting the rate at which operating fluid may flow out of said second operating means to an amount less than the rate at which said operating fluid may flow into said second operating means.

l0. In an apparatus for transferring headed fasteners and the like, an inclined raceway for slidably supporting a plurality of fasteners with their heads uniformly oriented with respect to each other, a downwardly inclined sleeve rotatably mounted adjacent the lower end of said raceway, a delivery conduit communicating with the lower end of said sleeve, a slot formed in said sleeve whereby a fastener sliding down said raceway will fall into the sleeve when the slot faces the raceway and will be prevented from doing so when the slot faces away from the raceway, means normally maintaining said sleeve in a position wherein its slot faces away from said raceway, first fluid operated means opposed to said sleeve maintaining means and operable to rotate said sleeve to a position wherein its slot faces said raceway, movable means for retaining fasteners in and for releasing fasteners from said raceway, second fluid operated means normally maintaining said retaining and releasing means in a position to release fasteners from said raceway and operable to move said retaining and releasing means to a position wherein it retains fasteners in said raceway, a first fluid passageway for directing a flow of pressurized operating fluid from an external source into and out of said second operating means, a second fluid passageway for directing a flow of pressurized operating fluid from said second operating means to said first operating means only when said retaining and releasing means is in position to retain fasteners in said raceway, and a check valve interposed in said first fluid passageway for retarding the rate of flow of operating uid out of said second operating means.

References Cited in the file of this patent UNITED STATES PATENTS 786,835 Perkins Apr. 11, 1905 846,806 Skipps.. Mar. 12, 1907 1,060,377 Stutzer Apr. 29, 1913 1,703,458 Ruff Feb. 26, 1929 2,534,140 Moore Dec. 12, 1950 2,785,400 McIlvin et al. Mar. 19, 1957

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