Fastener Inserting Machines

Abstract

A machine for successively installing fasteners, especially the pull-to-set-type blind rivet-mandrel assemblies, wherein the fasteners are fed uniformly oriented in a vertical plane from a source of supply to a pickoff locality. An installing head is reciprocable in a parallel plane between a fastener inserting locality and a retracted fastener receiving position, and a transfer device is operative between the pickoff locality and the receiving position successively to reorient and present the fasteners for insertion by the head in a work piece or work pieces.

Description

BACKGROUND OF THE INVENTION

Fasteners of the rivet-mandrel-type commonly comprise a hollow rivet having a preformed flange at one end and a naillike mandrel extending axially through the rivet. The mandrel has a head larger then the rivet bore whereby, upon insertion of the rivet barrel in a hole in a workpiece from one side thereof, a relative retraction of the mandrel stem causes the head radially to expand the blind or inaccessible nonflanged end of the rivet as its flanged end is held against movement relative to the workpiece.

A variety of tools have been provided, usually of portable or hand held construction, with which to set pull type mandrel rivets. Such tools are manually loaded with the individual rivet assembly to be installed. Also, for industrial production purposes, there is as disclosed, for instance, in U.S. Letters Patent No. 3,367,166, issued Feb. 6, 1968 on an application filed in the name of Albert E. Newton a mandrel rivet inserter having means for axially feeding successive fasteners automatically. No mandrel rivet inserting machine is known to be available, however, which is adapted to be automatically fed from a raceway, or for automatic use as a part of an assembly line wherein workpieces progress subsequently from one operating station to the next.

SUMMARY OF THE INVENTION

In view of the foregoing it is a primary object of this invention to provide an improved cyclically fed machine for installing fasteners, for instance pull-type mandrel-rivets, at a station of an automatic assembly line or independently at a bench where workpieces are to be presented thereto at a rapid rate.

To the ends stated, the present invention contemplates a machine for inserting blind mandrel rivets comprising a riveting head mounted on a guideway for reciprocation in a vertical plane to and from a workpiece, a raceway inclined in a vertical plane spaced from the head and adapted to feed successive mandrel rivets with the mandrels uniformly depending from their rivets, and a transfer device for receiving successive endmost mandrel-rivets in the raceway and operative to invert and present them individually to the retracted head for insertion. An operative stroke of the head desirably is initiated in response to arrival of a workpiece in proper registry therewith. As herein shown, the transfer device is operatively connected to the inserting head.

The illustrative riveting head includes a work engageable abutment and a bore extending therethrough adapted to receive each mandrel stem of the fasteners as presented by the transfer device. A further feature of the invention resides in the arrangement whereby there is an adjustable angle of operation of the head in its plane relative to the inclination of the raceway, and the transfer device includes a fastener carrier mounted for reciprocation along and predetermined rotation about a horizontal axis, an operating linkage permitting lost motion of the carrier. A further feature relates to the provision of means for angularly adjusting the operating path of the head about the axis of rotation of the carrier to facilitate versatility in setting up the machine in an assembly line.

DESCRIPTION OF THE DRAWING

The foregoing and other features of the invention, including various novel details and combinations of parts, will now be more particularly described in connection with a preferred embodiment and with reference to the accompanying drawings thereof, in which:

FIG. 1 is a view in right-hand side elevation of a machine for installing blind mandrel-rivets;

FIG. 2 is a view in front elevation of the machine shown in FIG. 1 and looking in the direction of the arrow A there indicated;

FIG. 3 is a bottom view, partly in section, of a portion of the machine shown in FIG. 2, a fastener transfer device being in its advanced position;

FIG. 4 is a fragmentary view taken on the section IV-IV of FIG. 2;

FIG. 5 is a detail view taken on the section V-V of FIG. 3;

FIG. 6 is a view, partly in section, of the lower end of a raceway and the transfer device in retracted or pickoff relation, the parts being viewed in the direction of the arrow A of FIG. 1;

FIG. 7 is a left-hand side elevation, and partly in section, of parts shown in FIG. 6;

FIG. 8 is an enlarged fragmentary view of the transfer device and a mandrel rivet therein;

FIG. 9 is a section taken on the line IX-IX of FIG. 6;

FIG. 10 is a view in enlarged elevation, with portions broken away, of a riveting head shown in FIGS. 1 and 2;

FIG. 11 is an enlarged view of the rivet, shown unset in FIG. 10, when secured in workpieces; and

FIG. 12 is a diagram of the fluid pressure control means of the illustrative machine.

DESCRIPTION OF A PREFERRED EMBODIMENT

The illustrative machine will be described as applied to setting a fastener 14 (FIGS. 1, 7, 10 and 11) comprising a rivet 16 and a mandrel 18 for the purpose of assembling workpieces, for example a tag 20 and sheet metal 22. It may be assumed that automatic means (not shown) is provided for successively registering pieces 20, 22 beneath the machine, and with rivet receiving holes aligned, on a work support or carrier W. The machine has a base 30 (FIG. 1) including opposed spaced side plates 32, 34 secured by cross bars 36. Mounted on the base 30 as will next be described are a rivet inserting head 38, a mandrel-rivet feeding means including a vibratory supply hopper 40 with cooperative raceway 42, and a transfer means generally designated 44 for picking off successive mandrel rivets 14 from the raceway and presenting them in uniformly reoriented position to the head 38 for insertion.

The head 38 (FIGS. 1--3 and 10) has a body portion 46 slidable heightwise in a guideway 48 having straight opposed channels for respectively receiving guides 50 secured to the body portion 46. Preferably the guideway 48 is angularly adjustable in a vertical plane, and in the FIG. 1 is shown as upwardly and rearwardly inclined at about 10.degree. from vertical. For thus supporting the guideway, a block 52 (FIG. 2) is rotatable about a horizontal axis as permitted by a bolt 54 extending through the side 32 and threaded into a bore of the block 52, the guideway 48 lying in a groove of the block and being engaged endwise by the bolt 54.

The tool head 38 may be of any suitable type, preferably fluid pressure operated, a conventional commercial head being shown by way of illustration in FIG. 10. Its internal construction is briefly described hereinafter, it sufficing for the moment to note that a rivet-abutting nosepiece 55 is provided. The tool body portion 46 is reciprocated during operation of the machine along the guideway 48 by a double acting cylinder 56 (FIGS. 1--3 and 12) secured parallel thereto by a bracket 58. A piston rod 60 (FIGS. 1 and 12) projects from the cylinder 56 and is coupled by a yoke 62 and a pin 64 to one of the guides 50. Accordingly the arrangement is such that in inoperative position the tool body 46 is held in a raised or retracted position by pressure in the cylinder 56 beneath its piston. An operative stroke is effected downwardly in the course of a cycle of the machine upon fluid pressure being admitted above the piston, the limit of downward movement of the body 46 being simultaneously determined by the workpiece 22 and an adjustable stop screw 66 fixed in a bracket 68 secured on a lug 70 of the body portion 46. As more clearly shown in FIG. 4 this connection is effected by a bolt 72. At the lower end of the stroke the stop screw 66 shifts a spring return control valve 74 (FIGS. 1, 2 and 12) later referred to and supported by a bracket 76 secured to the guideway 48. It is to be noted that the bolt 72, for a fastener-feeding purpose later mentioned, also pivotally supports an actuating lost-motion link 78 one end of which is coupled to the body portion 46.

For supplying and presenting successive mandrel rivets in properly oriented position (as indicated in FIG. 2) and coaxially aligned for reception in the nosepiece 55 of the inserting head 38, feed means comprising the hopper 40, the raceway 42, and the transfer means 44 are provided as next explained. The rivets 16 assembled on their mandrels 18 are individually conducted out of a random mass in the hopper by its vibratory action and introduced singly into the mouth of the inclined raceway 42. The fasteners slide downwardly with their preformed rivet flanges supported on spaces parallel raceway bars 80, 82, the mandrel shanks depending between the bars. The raceway is rigidly supported on the base 30 by brackets 84, 86. As the fasteners thus descend under the influence of gravity, and being restrained in the raceway by a cover strip 88 (FIGS. 2, 6 and 7) secured to the bar 80, they reach an endmost position wherein a pickoff locality is defined by brass inserts 90, 92 (FIGS. 6 and 7), which may be of other nonmagnetic material when desired, respectively secured to the bars 80, 82 by bolts 94. The lower end of the insert 92 angularly projects to form upper and lower fastener arresting or positioning surfaces 96, 98, respectively. For this purpose the upper surface 96 is spaced from the lower extremity of the cover strip 88 by a distance permitting passage of the tubular portion of a single lowermost rivet 16, and the lower surface 98 is spaced from the lower extremity of the bar 80 only sufficiently to allow passage therebetween of a single mandrel stem. The inclination of the raceway being on the order of 45.degree., the axis of each lowermost mandrel is also inclined forwardly and in a vertical plane at a corresponding angle of 45.degree.. The flange of the rivet in this pickoff locality rests on a flat upper surface 100 of the insert 92, and accordingly the to next to be transferred to the head 38 may be separated from the raceway 42 as next explained.

The transfer means 44 comprises, in coaxial alignment with the bolt 54, a reciprocable outer sleeve 102 (FIGS. 3, 5, 6) slidable on a horizontal inner sleeve 104, and a fastener-carrying shaft 106. For insuring correct angular orientation of each fastener when presented to the head 38, means is provided as will now be described of rotationally adjusting the inner sleeve 104 about its axis in accordance with corresponding adjustment of the head guideway 48. Thus a flange 108 (FIGS. 3 and 6) of the sleeve 104 is mounted in a bore 110 in a split clamp portion of the side plate 34, and a line 112 (FIGS. 2, 3 and 6) secured by a bolt 114 to the block 52 is secured in adjusted angular relation to the sleeve 104 by a stud 116. The stud 116 is threaded through a tapped hole in the link 112, and an inner end of the stud projects into a cam groove 118 formed in the carrying shaft 106 to control inversion of the fasteners during their transfer from the raceway. For maintaining constant angular relation between the block 52 and the line 112, a hollow, square sectioned spacing bar 120 (FIGS. l, 2 and 3) receiving the bolt 114 has its ends fitted in square recesses in the block 52 and the link 112.

In order to operate the transfer means 44 in cyclical time relation to the operating strokes of the head 38 the outer sleeve 102 is horizontally actuated by means of the link 78 the lower end of which is formed with an elongated lost-motion slot 122 (FIG. 3) for receiving a bolt 124 threaded into a boss 126 on the sleeve 102. It will be understood that another boss such as that designated 128 (FIG. 3) may be provided for coupling to a boss 130 of the head 38 when other angularity of the head guideway 48 requires. In the event assembly operations necessitate that the head guideway be disposed horizontally between the side plates 32, 34, the link 78 may be replaced by one of offset or crank shape to avoid interference with the raceway.

Referring to FIGS. 3, 6 and 9, the left end of the retracted carrier shaft 106 has a channeled face 132 lying in a plane parallel to the axis of the lowermost mandrel fastener. A complemental spacing plate 134, a brass shroud 136, and permanent horseshoe-shaped magnet 138 are secured against the face 132 by a bolt 140. The arrangement is such that the shroud 136 embraces a central portion of the magnet leaving its upper and lower right angled recesses 142, 142 exposed to engage and pick off the lowermost mandrel 18 upon feeding movement of the transfer means 44 toward the left and away from the raceway.

The groove 118 curves along the circumference of the shaft 106 to cause it to turn through a predetermined angle (about 55.degree. as shown) corresponding to the difference in inclination between a mandrel in the raceway and what its inclination must be to be correctly reoriented and presented for reception in the bore of the nosepiece 55. Opposite end portions of the groove 118 are parallel to the axis of the shaft 106 but offset angularly about the axis to compensate for the difference in inclination of a mandrel in the raceway pickoff position and in the reoriented presenting position required by the angularly adjusted guideway 48. (Since the raceway 42 generally remains fixed, a change in the inclination of the guideway 48 usually requires substitution for the shaft 106 of another having its groove 118 angularly extending an appropriate distance about its axis. These changes are of course dictated by the needs of the particular work on which the machine is to operate.)

To enable the shaft 106 and hence its fastener carrying magnet 138 to be horizontally shifted between pickoff and delivery positions in response to reciprocable movement of the outer sleeve 102 over the inner sleeve 104, a longitudinal slot 144 (FIG. 3) in the sleeve 104 slidably accommodates a block 146 (FIGS. 3 and 5), the block threadedly receiving a grub screw 148 radially extending into the outer driving sleeve 102. As best shown in FIG. 3, the right end of the shaft 106 is reduced to extend axially through a bearing 150, a washer 152, and lock nuts 154, 154 threaded thereon. The nuts 154 adjustably determine relative axial position of the shaft 106 and the other sleeve 102, a compression spring 156 yieldably bearing endwise on a shoulder of the shaft and contained by the bearing 150 to urge the shaft toward the inserting hear 38.

The position of the magnet 138 is such that it holds the mandrel-rivet being picked off the raceway by the shoulders of the recesses 142 a distance about equal to the shaft radius from the axis of the shaft 106. Accordingly as the magnet moves to the left, i.e., toward the angularly reoriented rivet-down presenting position beneath the head 38, the shaft 106 itself serves to retain the next endmost fastener in the raceway until the shaft is again retracted to enable the magnet recesses 142, 142 to align with the surfaces 96, 98.

A cycle of operations is preferably initiated by the workpieces 20, 22, being registered with the head 38 and thereby shifting a control valve 180 from its rest position shown in FIG. 12. The reciprocable riveting head 38 will be briefly described in connection with an operating cycle of the machine, reference being had mainly to FIGS. 10 and 12. It will be recalled that the head 38 had initially been held retracted by means of the cylinder 56, the transfer means 44 then being in advanced position to hold a mandrel-rivet reoriented for reception axially in the nosepiece 55. The tubular nosepiece 55 is secured to the lower end of an extension 160 of the tool body 46. Mandrel pulling means includes a conventional chuck 162 operated axially by a spring-return piston (not shown) preferably hydraulically actuated in a cylinder in the body 46. Following descent of the head 38 from its position (shown in (FIGS. 1--3) to cause the nosepiece 55 to actually receive the presented mandrel in the now stationary shaft 106, the transfer means 44 retracts without yet commencing rotation of the shaft. The descending nosepiece removes the fastener from the magnet 138, the rivet bearing on an ear 164 of the shroud 136 until the rivet flange is engaged by the nosepiece 55. Then, as the nosepiece descends further to press the rivet flange against the sheet 22 the shaft 106 rotates about its axis as it retracts to remove the ear 164 and enable the fastener to be thrust into the workpiece holes. A spring detent 166 in the nosepiece lightly engages the mandrel stem to prevent its falling out. Pressure fluid from an intensifier 168 (FIGS. 1 and 12) is admitted via a hose 170 to the cylinder and beneath the piston therein to effect a rivet setting stroke of the chuck, mandrel pulling being initiated by cooperative gripping jaws 172 of the chuck upon actuation of the valve 74 (FIGS. 1 and 12) as above mentioned to open an exhaust line 174.

The head 38 is normally held in its upwardly retracted position by virtue of fluid pressure (preferably air) in a main line 176 (FIG. 12) being communicated via a hose 178 to the under side of the piston in the cylinder 56. A branch from the line 176 passes through the valve 180 to a reservoir 182, a valve alternatively closing a path from the line 176 to the reservoir and opening one from the reservoir 182 through a hose 186 to the upper end of the cylinder 56 effecting descent of its piston rod 60. As above indicated the consequent lowering of the head 38 also causes the link 78 to retract the transfer means 44. During retraction of the chuck jaws 172 while gripping the mandrel, nosepiece 55 holds the rivet against retraction. The mandrel is tensioned to upset the blind end of the rivet and thereafter is usually broken off at a reduced stem portion within the rivet. The broken mandrel stem within the head 38 may be pushed rearwardly by subsequently inserted mandrels until it drops out of a tube 188.

When in the course of each cycle the head 38 is in its retracted position, mandrel pulling is initiated by actuation of the valve 74 as mentioned above. In order to insure that the gripping jaws 172 will close on the mandrel prior to exerting tension, a rotary valve 190 (FIGS. 1 and 12) provides for decreasing fluid pressure in the cylinder 56 above its piston very shortly after the valve 74 opens the exhaust line 174. The chuck 162 has a detachable front end having an internal frustoconical face 192 (FIG. 10) against which the jaws are urged by an axially bored pusher 194. The pusher and the nosepiece 55 are inclined to the axis of the head 38 so that a spring 196 normally urges the jaws apart to open condition, but the retraction of the chuck 162 as aforesaid causes mandrel gripping followed by mandrel pulling. The slightly delayed operation of the valve 190 is effected by its operating mechanism now to be described. Pivoted to a lug 200 (FIG. 1) on the body 46 is a link 202 for actuating the valve 190. The link 202 has a slot 204 slidably carrying a pin 206 secured in a lever 208 of the valve 190, which itself is bracketed to the cylinder 56. As shown in FIG. 1 the lever 208 is urged clockwise by a spring 210 having one end connected to an arm 212 of the valve 190. After lost motion between the link 202 and the pin 206 as the head reached its advanced position, the lever 208 rocks a spool of the valve 190 to open the line between the reservoir 182 and the valve 180 to exhaust, whereupon rivet setting progresses as the mandrel is tensioned and is broken. Then fluid pressure below the piston of the cylinder 56 causes retraction of the head 38, the spool of the valve now being rocked back to close that valve.

Meanwhile, with advance and retraction of the head 38, the transfer means 44 has retracted to pick off another mandrel rivet 14 and returns to reorient and present it for setting in the next cycle. Departure of the workpiece with its installed fastener from the valve 180 connects the latter again to the main pressure line 176 to recharge the reservoir 182.

It will be apparent that if fasteners having other than steel mandrels are to be installed by the machine, other holding means (for instance suction) can be employed in lieu of the magnetic means herein proposed.

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

Claims

I claim:

1. A machine for installing mandrel rivets in a workpiece comprising a raceway inclined in a vertical plane for feeding successive mandrel rivets from a supply and in rivet-up condition to a pickoff position, a riveting head reciprocable to and from the workpiece and operative in a plane spaced from and parallel to that of the raceway, said head being adapted to receive and set mandrel rivets when in rivet-down condition, and transfer means operative in time relation to the head to receive successive mandrel rivets at the pickoff position, and reorient them for presentation adjacent to the workpiece and in alignment with the head when the head is retracted.

2. A machine as set forth in claim 1 wherein said transfer means is operatively connected to means for reciprocating said head.

3. A machine as set forth in claim 2 wherein said transfer means is reciprocable along and about an axis, and means is provided for angularly adjusting the operating path of the head about said axis.

4. A machine for installing mandrel-rivets in a workpiece piece comprising an inserting head reciprocable toward and from the work piece, said head including a tubular end for abutting a flange of each rivet to be set and for receiving its mandrel, and means relatively retractable along an axis extending through said tubular end to tension the mandrel therein, power means for controlling reciprocation of the head and said retractable means, and feed means operable by said power means for transferring successive mandrel rivets cyclically from a random mass thereof and into alignment with said axis for reception in said end, said feed means comprising mechanism disposing successive mandrel rivets at an angle to and offset from said axis, and transfer means movable to carry a mandrel rivet between the offset position and a presenting position on said axis, said transfer means being rotatable to invert successive mandrel rivets during transfer by substantially said angle.

5. A machine as set forth in claim 4 wherein the transfer means is movable along a horizontal axis in time relation to the reciprocation of said head, and the operating path of the head is angularly adjustable about said horizontal axis.

6. A machine as set forth in claim 4 wherein the feed means includes an inclined raceway, and the transfer means includes a fastener-carrying shaft movable axially and about its axis, and fastener holding means including aligned mandrel engaging shoulders offset from the shaft axis and arranged to pick off successive fasteners from the raceway, a surface of the shaft serving during transfer to retain other fasteners in the raceway.

7. A machine as set forth in claim 6 wherein the holding means is in the form of a permanent horseshoe-shaped magnet.

8. A machine as set forth in claim 6 wherein the shaft is formed with a cam groove curved along its circumference to determine the angular movement of the shaft during fastener transfer and orientation.

9. A machine as set fort in claim 8 wherein the transferring means is operatively connected to the head by linkage including a lost-motion means, and said curved groove in the fastener carrying shaft has terminal portions substantially parallel to the axis of said shaft.