US2132113A - Rivet setting mechanism - Google Patents

Description

wm-a3 s sheets-Shen 1 @c 4, 1938@ L. Q HUCK RIVET SETTING MECHANISM original Filed may 14, 1935 @at 4, 33 L, Q, HUCK RIvEjr SETTING mcmxms origami Filed may 14, 3535 3 Shams-Sheet `2 INVENTOR. olas Haci OCL 4, L.. C. HUCK RIVET SETTING MEcHANIsM original Filed Mayvm, 193s 5 sheets-sheet 3 Patented Oct. 4, 1938 RIVET SETTING MECHANISM Louis C. Huck; Buchanan, Mich., assignor to Buxon Holding Corporation, a corporation of Michigan original application May 14, 1935', serial No. 21,472. Divided and this application June 22,

1936, Serial No. 86,571

10 Claims.

The invention relates to a rivet setting mechanism and it has particular relation to a mecha,- nism for setting rivets of a type including a tubular element and a pin extending therethrough and which is inserted and set from one side of the structure to be riveted.

More particularly the invention constitutes an improvement in rivet setting mechanisms over those disclosed in the copending applications for patent of Louis C. Huck et al., Serial No. 615,544, filed June 2, 1932, now Patent 2,053,718, granted Sept. 8, 1936, and Louis C. Huck et al., Serial No. 636,480, tiled October 6, 1932, now Patent 2,053,719, granted Sept. 8, 1936. This application l constitutes a division of my copending application for patent, Serial No. 21,472, filed May 14, 1935.

. In the rst of the above mentioned copending applications for patent a. rivet setting mechanism was set forth which included a rivet setting gun and a iluid pressure boosting device connected thereto by ilexible tubing so that the gun might be used at points remote with respect to the booster and without moving the booster each time the gun would be moved. It also was set forth in this application for patent that air pressure would be used in the booster device for building up a liquid uid pressure which would be supplied to the gun for operating it during the rivet setting procedure. Moreover, this rivet setting mechanism was so designed and constructed that by manipulating a trigger on the gun, operation of the booster device and setting of the rivet could be controlled entirely by the operator manipulating the gun even though the booster device would be located at some distance away.

In the above mentioned copending application vfor patent, Serial No. 636,480, filed October 6, 1932, a rivet setting gun of somewhat diierent character is disclosed which also operates in conjunction with a booster device such as set forth in the iirst mentioned copending application for patent. The gun in the second case includes two pistons one of which operates rst when the trigger on the gun is pulled to eiect a certain phase of the rivet setting operation and then upon completion of this phase, the second piston automatically becomes operative to cause an auxiliary anvil to move over the head of the tubular part of the rivet to radially contract a portion thereof o into grooves in the pin forming a part of the rivet. Upon completion of this operation, the

liquid fluid pressure is automatically increased to such extent that the rst piston continues its movement to break the pin at a predetermined 5 Point.

satisfactory, certain improvements have been def sirable and form the basis of this invention. These may generally be indicated in the objects of the invention but a more detailed explanation wm be fourd in che description. objects of the invention additional to those outlined hereafter will be apparent from this description, from the drawings to which it relates and from the claims hereinafter set forth.

` One object of this invention is to provide a rivet setting gun which is more eicient in operation and which may more easily be handled and manipulated by the operator.

Another object of the invention is to provide an improved jaw mechanism and operating arrangement therefor which will enable using a smaller diameter of barrel on the gun and also facilitate insertion of the jaws during assembly of the gun. f

Another object of the invention is to provide an improved riveting gun or the like employing jaws therein, wherein means are provided for manually opening the jaws.

For a better understanding of the invention reference may be had to the drawings wherein: l

Figure 1 is a longitudinal, cross-sectional view of a riveting mechanism constructed according to one form of the invention;

Fig. 2 is an end view of the mechanism as seen from the left end of Figure 1;

Fig. 3 is a cross-sectional view taken substantially along the line 3-3 of Fig. 2;

Fig. 4 is a cross-sectional view taken substantially along the line 4--4 of Fig. 3;'

Fig. 5 is a cross-sectional view taken substantially along the line 5-5 of Fig. 4;

Fig. 6 is a cross-sectional view taken substantially along the line 6--6 of Fig. 1;.

Fig. rI is a cross-sectional view takenv substantially along the line 'l-l of Fig. 1;

Fig. 8 is a cross-sectional view taken substantially along the linefB-B of Fig. 1;

Figj9 is a fragmentary cross-sectional view of a riveting mechanism constructed according to another form of the invention;

Fig. 10 is a cross-sectional view taken substantially along the line llt-l0 of Fig. 9;

Fig. 11 is a cross-sectional view illustrating a rivet inserted in openings in a structure to be riveted as seen prior to setting of the rivet; and

Fig. 12 is a view similar to Fig. 11 illustrating the assembly after the rivet has been set.

Since this application is a division of the copending case, Serial No. 21,472, the means for supplying fluid under pressure to the riveting mechanism herein disclosed has not been included. The riveting mechanism is connected to the iiuid pressure supply means solely by means of two conduits and these have been included herein and are identified by the numerals 24 and |23. These numerals correspond to the numerals identifying the same conduits in the parent case. Conduit 24 supplies liquid which may be subjected to high pressure during the rivetl setting operation. The conduit |23 4is an air supply line, which not only supplies air to the riveting mechanism, but which also provides a means for controlling the remote pressure developing means through operation of a trigger on the riveting mechanism.

vReferring now to Figs. 1 and 2, the riveting gun comprises a cylinder casting |10 having a thickenedupper portion |1| upon which a handle |12 is detachably secured by means of bolts |13. It may be stated at this time that the gun normally will be used with ythe handle uppermost and the 4latter is so arranged with respect to the cylinder casting and other parts of the gun that a vertical line substantially through the center of gravity of the gun will pass upwardly substantially through the center of the handle so that the operator holding the gun suspended from the handle will find the axis of the cylinder substantially horizontal. This adds'to the ease with which the gun may be .manipulated and operated. 'I'he casting |10 includes two bores |14 and |15 separated by an integral wall |16, and a tubular piston rod |18. is journaled in a bearing |19 provided in a central opening in the wall |16 for reciprocatory movement axially of the bores. The bearing terminates at its right end in a flange which abuts a shoulder |8| on the wall so as to prevent movement of the bearing towards the left, and at the right of the flange |80 a sealing ring |82 of cup-shaped character is provided so as to positively prevent fluid at the right side of the wall |16 from owing along therod |18 to the left side thereof. A piston |84 is rigidly mounted on the rod |18 within the bore |14 and this piston has a sealing ring |85 at its left side and around the rod to positively prevent nuid between the piston and the wall |16 from owing between the piston and piston rod. 'I'he outer periphery of the piston is provided with sealing rings |86 similar to those mentioned which prevent uid from flowing between the cylinder wall and the piston periphery. At its right end, the piston rod projects through a closure head |81 held against a shoulder |88 by a ring |89 threaded into the end of the cylinder, and the head |81 has a bearing |90 through which the rod projects. The inner end of this bearing is anged similarly to the bearing |19 and a sealing ring is disposed in a recess in the head to prevent uid from flowing between the piston rod and the head.

In the bore |15 a similarpiston |94 is provided but this piston has an inner bearing associated therewith which may reciprocatev with the piston on the piston rod |18. This bearing terminates at its right end ln a ange |98 and a sealing ring |91 similar to those mentioned is mounted on the right end face of the piston for preventing fluid at the right side of the latter from owing between the piston rod and the bearing. The left side of the piston terminates in a tubular portion |98, which may reciprocate in a flanged bearing |9lsecured 'in an apertured head 200 that is held in the left end of the cylinder by a threaded sleeve 20|. A sealing ring such as mentioned may be provided at the right side of the head 200 to prevent uid from escaping along the bearing.

At the left end of the tubular portion |98 of the piston |94, a. head 203 is mounted for reciprocatory movement on the piston rod and a bearing 204 may be provided between it and the rod,- and this head has a tubular portion 205 slldable in bearing |99, and which abuts the portion |98 of the piston so that when the piston is moved to the left, the head 203 moves therewith.

The head 203 at its left end terminates in three radially offset and axially directed legs 206 spaced degrees apart as best shown by Fig. 6, and these legs are axially movable in recesses 201 formed in the cylinder head 200. Between the recesses inwardly directed legs 208 arethereby formed on the head 200, as also shown by Fig. 6, and it may be noted that the circumferential length of the recesses substantially is the same as the circumferential length of the legs 208. Referring now both to Figs. 1 and "l, axially beyond the end of the legs 208,-the head 200 terminates in a cylindrical portion 209 of larger i diameter and this tubular projection has Atwo rslots 2|0 spaced 60 degrees apart and which extend to the outer end thereof. An outer barrel sleeve 2|2 is reciprocable in the tubular portion 209 and the inner end of this sleeve at one point is provided with an outwardly directed projection 2|3 adapted selectively to t in one of the openings 2|0. It will be appreciated that -the slot 2|0 will hold the barrel sleeve 2 I2 against turning while permitting its reciprocatory movement and that by withdrawing the barrel, it may be re-inserted with the projection 2|3 disposed in the other slot 2|0 thereby positioning the barrel sleeve in a 60 degree displaced position. Reciprocatory movement of the sleeve 2|2 is additionally guided and supported by a sleevel 2|4 (Fig. l1) threaded into the end of the sleeve 20|, and it will be apparent that sleeve 2|4 will normally prevent withdrawal of the bari'el sleeve 2|2 by abutment with the projection 2|3 on the latter. An inner sleeve 2li is reciprocatory in the sleeve 2|2 and the former, as best shown by Fig. 7, has three circumferentially spaced slots 2|6 of the same character as the slot 201 shown by Fig. 6, and these slots receive radial projections 2|1 at the inner end of the sleeve 2|2. From this description it will be appreciated that the two sleeves may reciprocate relative to one another and, with the parts arranged as shown by Fig. 1, the legs 206 on the head 203 are in4 engagement with the projections 2|1 on the sleeve 2|2, while the endportions'of the sleeve 2|5 between the slots 2I6 are in engagement with the radial projections 208 on the head 200.

It will now be apparent that if piston |94 moves to the left, itwill move the head 203 to the left and the engagement of the .legs 206 on the -latter with the projections 2|1 on sleeve 2|2 will cause the latter to Vmove to the left. The sleevev2|5 may remain stationary and in abutment with the legs 208 on the cylinder head 208 as the legs 206 and 2|1 on the head 203 and sleeve 2|2 may move axially in the slots 2|6 in the sleeve. reversed by removing the sleeve 2|4 and withdrawing the sleeves 2|2 and 2| 5 and then reinserting them with the projection 2|3 on the outer sleeve dispod in the other of the slots This arrangement may be -tubular element 230.

2|0, and the reason for this selective arrangement is to enable setting yof different types of rivets as set forth in the previous applications for patent mentioned.

The outer end of the piston rod |18 has an enlarged portion reciprocatory in the inner sleeve 2|5 and a reduced portion 22| threaded into a tubular jaw operating member 222 that is also reciprocatory in the sleeve 2|5. The member 222 at its outer end has a conical inner periphery 223 terminating at the end of the member in a circular opening, and as best shown by Fig. 8, this conical surface has three equally spaced grooves 224 of cylindrical character with the axis of each cylindrical surface substanti-ally parallel to the conical surface. These grooves respectively receive jaws 225 having outer cylindrical surfaces seated in and movable along the grooves. From this it should be appreciated that the jaws m-ay be expanded or contracted by their movement along the grooves 224 while still obtaining full and cylindrical surface contact between the jaws and the grooves. It will be noted that the grooves are not greater than semi-circular in cross section and this is advantageous in that it permits inserting the jaws through theinner end of the jaw operating member 222. If the jaws had to be inserted through the front opening at the smaller end oi the conical surface 223, a larger diameter of the member 222 would be required and this in turn would require larger diameters of the sleeves 2|2 and 2|5 and hence the barrel of the gun would be larger land could not be inserted in certain places for riveting.

Each of the jaws has an axial extension at its inner end as indicated at 221 that has a. slot 228 therein for receiving one of three radial projections 229 on the outer end of a tubular sleeve 230, which extends entirely through the piston rod in a reciprocatory manner and projects from the right end thereof. This construction enables manually pulling the jaws to the right relative to the operating member 222 by pulling the outwardly projecting end of the tubular member 230 and this may be advantageous after the riveting operation in the event the jaws are unduly wedged in the grooves 224. For normally urging the jaws toward the left, a sleeve 23| is slidable on the sleeve 230 and is provided with an annular shoulder 232 engaging the ends of the projections 221 on the jaws. This sleeve is urged toward the left by a coil spring 233 engaging the right end of the sleeve and which is disposed in a recess 234 provided between the larger portion 220 of the piston rod and the Between the ange 232 on the sleeve 23| and theend of the piston rod portion 22|, an annular ring 235 of rubber or the like is provided for cushioning the jaws when the rivet pin breaks and when the jaws tend to quickly move to the right with respect to the operating member 222 as the result of recoil. It may be noted here that normally this will be the action obtained so that the jaws will automatically' free themselves from any wedging engagement with the grooves 224 as a result of recoil force when the pin breaks, but in the event this does not occur or for any other reason it is desired to move the jaws to the right relative to the member 222, the right end of the sleeve 230 may be gripped from the exterior of the gun and the sleeve pulled to move the jaws.

The inner surfaces of the jaws are generally cylindrical with the axis thereof substantially coinciding with the axis of the piston rod and such inner gripping surfaces are provided with grooves for gripping a grooved portion of the rivet pin. For engaging the tubular part of the rivet, the outer end of the sleeve 2|5 terminates in an anvil 231 that has a tubular projection 239, while the outer end of the sleeve 2|2 terminates in anIanvil 239 having a slightly tapered entry opening 240.

The right and outer end of the sleeve 230 has a short sleeve 24| secured thereon, such as by pins or a split ring 242, and this short sleeve has an enlarged bore at its left end containing a coiled spring 243 abutting the right endof the piston` rod |18. 'I'his arrangement insures movement of sleeve 230 with the piston rod |-18 when the latter moves to the right, so as to hold the lugs or ears 229 at the left end of the sleeve at the right end of the slots 228 in the jaws. In setting a rivet, breaking of the rivet pin causes the jaws to move to the right relative to the piston rod |18, and hence relative to sleeve 230, and if the lugs 229 were not at the right end of the slots 228 in the jaws, the jaws might engage the lugs and break them ol. It may be added that the length of the slots 228 to the left of lugs 229 (as shown in Fig. 1) is greater than that permissible movement of the jaws relative to the piston rod and member 222 as governed by the linear space between the shoulder 232 and the left end `of the piston rod portion 22|, so -that with the lugs 229 normally maintained at the right end of the slots 228, engagement of the lugs with the left end of the slots-upon breaking of the pin` ordinarily will not occur.

The sleeve 24| enables manual pulling of the sleeve 230 so as to move the jaws backwardly relative to the jaw openings 224. This isadvantageous if the jaws ever freeze in the openings, or if it is desired to expand the jaws for any reason.

Now referring to Figs. 3 and 4, the casting |1| at the upper side of the gun, has an opening 244 in communication with the air line |23 and this passageway in turn communicates with an opening 245 communicating with a valve passageway 246. The passageway 246 has a valve 241 therein provided with axially directed peripheral spaces 248 to allow air to flow therethrough, and the central portion of the valve is normally pressed against a valve seat 249 by means of a spring 250 engaging the valve and an apertured bushing 25| threaded into the passageway 245. The valve seat 249 has a central opening to allow air to pass therethrough when the valve is unseated, and this opening communicates with an opening 252 communicating with the atmosphere. For unseating the valve 241 a plunger 253 is reciprocable in a head 254 closing the left end of the passageway 246, and thisv plunger, as best shown by Fig. 1, is adapted to be moved by one end of a bell crank 255 pivoted on the handle as indicated at 256. The opposite end of the bell crank is engaged -by a short arm 251 rigidly connected to a trigger 258 that .is pivoted as indicated at 259 on the handle. Thus, when the trigger is raised, the plunger 253 is moved toward the right unseating the valve 241 and this in turn connects the conduit |23 to the atmosphere allowing airto exhaust.

Referring to Figs'. 3, 4, and 5, the passage 244 is in communication with the right end of the bore |14 and the left end of bore |15 in the gun. 'I'his is effected by providing 4a longitudinal passageway 265, as shown by Fig. 5, extending through the casting |1| at one side of the cylinder bores, and which has its ends plugged and this passageway is in communication with the bores` |14 and 15 by means of ports 266 and 261 and by providing a second port 268, as shown by Figs. 4 and 5, communicating vwith the right end bore |14 and with the passage 244. Now, if the trigger is pulled, the conduitl |23 and the passage 244 are opened to atmosphere and the space at the right side of piston |84 and the left side of piston |94 may exhaust to atmosphere. Conversely, when the trigger is released and the valve 241 closes, air under pressure may ow into tl space at such sides of the pistons |84 and i Referring also to Figs. 3 and 4, the liquid line 24 is threaded into a bushing 215 disposed in a bore 216 in the casting |1|, and this bushing is held against a seal 211 by a threaded bushing 218. l 'I'he bore 216 in turn communicates with an aperture 219, communicating in turn with a downwardly directed valve bore 280 extending diagonally into the wall |16 and communicating with the bore |15 by a smallerv opening 28| and with the bore |14 at the left end thereof,` as indicated'at 282. It may be noted that the sides of the wall |16 and pistons |84 and |94 are relieved so as to insure entry of liquid properly at the adjacent sides of the pistons even though the latter are at the ends of their strokes. The lower end of the bore 280 has an apertured valve seat 283 adapted to be closed by a ball v284 disposed in a sleeve 285 holding the 'seat in place and having its upper end enlarged and threaded into the upper end of the bore 280. A spring 286 in the sleeve presses the ball against its seat and the upper end of the spring is held by a cap 281 threaded on the sleeve. At its lower end, the sleeve has one or more openings 288 so that liquid flowing upwardly through the seat 283 may pass into the bore 280 at the outside of the sleeve. Thus, liquid may flow upwardly from the bore |15 and through the valve, but it cannot fiow in the reverse direction, while liquid may flow either to or from bore |14 through the bore 280.

For introducing liquid under pressure to the bore |15 at the right side of piston |94, a smaller opening 290 is formed in a tubular member 29| disposed in a bore 292 and this opening is in communication with the boreI 280 by means of an opening 293. The left end of the opening 290 is normally closed by a small valve element 294 integral with a stem 295 of larger diameter which may slide in the member 28|,and it will be noted that around the valve element 294 the end face of the stem is of larger diameter to provide a greater area for the oil to act upon once the element is unseated from the end of opening 290. Thestem 295 is urged toward the right to hold the element 294 in valve closing position by a strong compressive spring 296 disposed in a. tubular cap 291 threaded into the bore 292, and this spring abuts the left end of the cap at one end and at its other end a flange 300 integral with a plunger 30| which engages the stem 295. It will be seen that the'element 294 will not open until considerable pressure is applied and that once it opens, the larger area against which the liquid may act at the end of the stem 295 serves to hold the valve open even though the pressure should drop materially. The member 29| is held tightly in position by the cap 291 engaging a collar 302 that in turn engages a bushing 303 abutting the left end of such member 29|.

Suitable sealing rings 304 may be provided to prevent liquid from seeping between the stem, bore, bushing 303 and member 29|.

When the valve stem is moved by liquid pressure, it moves past a port 305 that communicates with an annular groove 3.06 lin the outer surface of member 29|, and the latter communicates with -an opening 301 extending to the cylinder bore |15. For the purpose of preventing movement of the stem by a pressure lower than that required to unseat the valve element in the event any slight leakage occurs past the latter when it is in closed position, the peripheral surface of the end portion of the stem -is -provided with very minute grooves 308 which will allow any oil seeping past the valve element 294 to iioW directly into the cylinder. If some means of this character were notprovided it is possible in the event of slight leakage past the valve element, that an oil pressure would be slowly built up against the end face of stem suilcient to move it and open the valve before reaching a pressure that alone would be suicient to unseat the valve element.

As best shown by Fig. 1, the system may be filled with oil by providing a tapered opening 3|0 in the casting |1| and tapered openings 3|| at each side communicating respectively with the two bores |14 and |15. After filling the system, the opening 3|0 is closed by means of a tapered plug 3|2 held tightly in place by means of a button 3|3 on a plate 3|4 that is secured by bolts 3 5 to the casting. For the purpose of facilitating removal of theplug 3|2, a screw 3|6 may be threaded thereinto and when screwed downwardly it may be engaged with the base of the opening 3|0 to dislodge the plug and force it upwardly.

Now referring to Figs. 11 and 12, the rivet may comprise a tubular element 325 having an intermediate portion of smaller internal diameter, an external head 326 and a tubular portion projecting from the opposite side of the structure to be riveted and which is indicated at 321. The rivet pin, which is indicated at 328, has a break neck 329 of smaller diameter than the remainder of the pin, a series of locking grooves 330 to the left of the break neck, a shoulder head 33|, a larger left end portionA 332, a head 333, and gripping grooves 334 at the opposite end of the pin. A spreader ring 335 is provided on the larger portion 332 of the pin and is adapted to increase in size whenthe head 333 engages it so as to provide a larger part for bulbing the tubular portion 321. of the tubular member.

When the rivet is set, the pin is pulled with the' reactionary force applied against the head 326, and this causes the head 33| rst to expand the larger intermediate portion of the tubular member, then the head 333 acting throughA the spreader ring 335 causes the tubular portion of the tubular member to bulb outwardly into a head as shown in Fig. 12, and then the head 326 is contracted radially to force metal into the locking grooves 330 which are then disposed within the head, and then further tension on the pin causes it to break at the break neck 329 then located at the outer side of the head 326. In setting the rivet, it is inserted as shown by Fig. 11 and the gunis moved into a position where the pin projects into the jaws 221 and it will be recalled that the jaws have grooves for receiving the grooves 334 on the pin. The operation of the system may now be described.

Assuming that the 'system is properly filled with oil and the air line connections are made, the gun is properly associated with the rivet pin and this brings the anvil portion 238 against the outer radial face of the rivet head 326. With the trigger 258 in closed position, air under pressure supplied through the conduit |23 is also supplied to the right end of the bore |14 and the left end of the bore |15 and this maintains the pistons |84 and |94 adjacent the intermediate wall |16 of the cylinder casting, it being understood that the liquid in the bores at the left side of piston |84 and at the right side of piston |94 is allowed to flow back through the conduit 24. When the trigger 258 is pulled, the line |23 is open to exhaust and this also opens the cylinder spaces in the gun at the right side of the piston |84 and at the left side of the piston |94 to exhaust. As described in the parent case, opening the conduit |23 to exhaust by operatingmtkhetrigger 258 causes actuation of a booster thati'n turn forces liquid through the conduit 24 and into the space at the left side of the piston |84. This causes the piston |84 to move toward the right, carrying with it the piston rod |18 and the jaw operating member 222. Positive and forceful contraction of the jaw members results lockingv them strongly to the rivet pin and continued movement ol the piston |84 will cause movement of the rivet vpin while the reactionary force is applied through the wall |16 and casting |18 and cylinder head 20D, sleeve 2|5 and anvil 231 to the face of the rivet head 326. The operations of expanding the tubular member intermediate its ends and formation of the bulbed head from the tubular portion 321 of the rivet are then eiected in order, and, after formation of this bulbed head, very strong resistance is encountered to further movementl of the rivet pin and this causes the liquid pressure in the barrel and in the liquid side to increase rapidly and when this pressure reaches a. predetermined amount `governed by the valve spring 296, shown in Fig. 4, the valve element 294 will be forced from its seat and the stem 295 will be movedto the left until liquid may llow into the cylinder bore |15 at the right side of piston |94. Then the piston |94 begins to move to the left moving with it the outer barrel sleeve 2 I2 and anvil 239 which forces the latter over the rivet head 326 and causes its radial contraction to force metal into grooves 330 of the pin. Upon contraction of the head 326 of the rivet, resistance to movement of either of the pistons |84 and |94 will further increase, and this will cause the liquid pressure in the system to build up to a point where the rivet pin will be so tensioned that it will break at the breakl neck 329. Ordinarily, when the pin breaks, the recoil force on the jaws will cause the jaws to move rearwardly and the broken part to pass rearwardly through the jaws and through the piston rod and sleeve 230 and to be ejected from the right end thereof.

If the trigger 258 on the. gun is now released, air pressure will again be built up in conduit 23 as the valve 294 will be closed, and air under pressure will be built up at the right side of piston |84 and at the left side of piston |94, causing these pistons to return to theiroriginal positions, thereby forcing the Vliquid at their opposite sides back through the conduit 24. As will be seen in Figure 4, the liquid at the right side of piston |94 may flow out of the cylinder bore |15 through the passageway 28| and past the ball 284 as the latter will be unseated by the pressure on the liquid due to the air pressure at the opposite side of the piston,

Figs. 9 and 10 illustrate an improved form of Jaw arrangement in the gun. Here the jaws 225 engage at their inner ends a relatively heavy,

sleeve does not pass through to the other end of the piston rod |18.l 'I'he spring 351 normally urges the inertia ring 354 and jaws forwardly and with the jaws in the normally operative position shown a substantial space 359 exists between the end of rod portion 22| and the ring.

'I'he jaws 225 are also and individually urged inwardly by springs having intermediate coiled portions 360 disposed in slots 36| in the member 222 and each coiled portion is pivotal on a pin 362 projecting through the slot. Frontwardly, the coils have ends 363 extending forwardly in recesses 364 in member 222, and which terminate in radial ends 365 projecting through small openings 366 in such member and into axial grooves 361 in the jaws, respectively. The other ends of the coils have radial ends `368 projecting into openings 369 in the jaws respectively, and by pressing against the rear walls of such openings, such ends urge the jaws individually away from the outer end of member 222.

When the rivet pin breaks, the large recoil force tends to throw the jaws back and relative to member 222, and it is important that the full force of this recoil not be absorbed by striking of the jaws against rod portion 22|. The spring 351 is occasionally not enough of a cushion against such force of the recoil. The ring 355, however, interposes an inertia force and its weight is such that the rearward throw of the jaws is slowed up owing to the fact that the jaws must pick up this weight and carry it with them, and while the jaws and ring both move rearwardly, the recoil force is dissipated enough that nal engagement of ring 355 with ,the end of rod portion 22| is not damaging to the jaws or ring. 'Ihe spring ends 365 and 368 do not interfere with movement` of the jaws and the ends 365 particularly maintain the jaws against turning or circumferential displacement. 'Ihe ends 368, while normally urging the jaws rearwardly, are not strong enough to overcome spring 351 so that the latter normally maintains the jaws seated in grooves 223 in member 222. These ends 368 are provided to move the jaws rearwardly and expand them when it is desired to withdraw an unset rivet gripped by the jaws, but manifestly it will be first' necessary to move sleeve 355 rearwardly before the ends 368 can perform this function. To move sleeve 355 rearwardly, an expanding tool 315 may be inserted from the right end of rod |18, and, while any suitable tool may be used, it is shown as comprising a tube 316 having segments 311 separated by slots 318, and a rod 319 threaded into the tube as indicated at 38|), and which has a tapered head 38| for expanding the segments. When the segments are expanded into gripping relation with sleeve 355 by turning rod 319 relative to the tube 316, the tool may be pulled to the right so as to move the sleeve.

Although more than one form of the invention has been illustrated and described in detail, itA

of the casing, a barrel sleeve extending axially from one end of the casing, a jaw enclosing and operating member in the sleeve and connected to one end of the rod, jaws in the member, said jaws and member having cooperating tapering surfaces, and means extending axially through the piston rod and engaging the jaws for manually moving the latter, said means extending beyond the opposite end of the rod for manual manipulation.

2. A rivet setting mechanism comprising a casing, a tubular piston rod and piston reciprocable in the casing, a jaw actuating member operatively connected to the piston rod, jaws adapted to be contracted and moved by said member, means extending axially through the rod and engaging the jaws for manually moving the latter, and resilient means for holding said first means normally in abutting and engaging relation with the Jaws.

3. A rivet setting mechanism comprising a casing, a tubular piston rod and piston reciprocable in the casing, a jaw actuating member operatively connected to the piston rod, jaws adapted to be contracted and moved by said member, means extending axially through the rod and having interlocking but play permitting engagement with the jaws vfor manually moving the latter, and resilient means for normally preventing play between the jaws and said first means.

4. A rrivet setting mechanism comprising a piston, a tubular piston rod, releasable gripping means operatively engaged by the rod at one end thereof, and means extending through the rod for releasing the gripping means.

5. In a riveting machine, a jaw actuating member, a plurality of separately movable jaws, means for urging the jaws into engagement with the jaw actuating member,and other means normally urging the jaws out of engagement with the member.

6. In a riveting machine, a jaw actuating member, a plurality of separately movable jaws, means for urging the jaws into engagement with .the jaw actuating member, and other means normally urging the jaws out of engagement with the member, the first means being more forceful than the second means.

7. In a riveting machine, gripping means for gripping and moving an element, means movable relative to the gripping means for applying gripping forces to the latter so as to grip and move the element, means carried by the second means and normally urging the gripping means into cooperative relation to said second means, and means also carried by the second means for urging the gripping means out of cooperative relation to the second means.

8. In a riveting' machine, a plurality of free jaws, a jaw actuating and contracting member, means urging the jaws into operative positions, and individual means for urging each jaw towards inoperative position.

9. In a riveting machine, a plurality of free jaws, a jaw actuating and contracting member, means urging the l laws into operative positions, and individual means for urging each jaw towards inoperative position, said individual means comprising springs anchored on the actuating member and respectively engaging the jaws.

10. In a riveting machine, gripping means for gripping and pulling an element, means for actuating and moving the gripping means, means normally urging the gripping means towards operative position, means urging the gripping means to inoperative position, and an inertia member separate from but movable by the gripping means.

. LOUIS C. HUCK.

atl

Images