US2390318A - Rivet ejector - Google Patents

Description

RIVET EJECTOR Filed March 3, 1942 3 Sheets-Sheet l CLAGGETT OFF'UTT INVENTOR.

38 38& I BY 1 7 ATTORNEY C. OFFUTT RIVET EJECTOR Filed March 3, 1942 3 Sheets-Sheet 2 INVENTOR.

CLAGGETT OFFUTT ATTORNEY.

Patented Dec. 4, 1945 UNITED STATES FATENT OFFME RIVET EJECTOR Claggett Ofiutt, Los Angeles, Calif.

Application March 3, 1942, Serial No. 433,177

2 Claims.

My invention relates generally to the art of riveting and more particularly to improved means of inserting rivets in their holes preparatory to the actual riveting operation.

Various devices have heretofore been offered to the trade for the holding of a plurality of rivets and for inserting them into their respective holes,

but so far asI am aware, none of these has been completely satisfactory. Most of the prior devices have either been too complicated or have been constructed in such manner that the operator had to learn a new technique of riveting in order to usethem.

It is the major obiect of my invention to pro- .vide a rivet ejector which the average riveter can use without unusual or excess movements,

which will enable him to increase his production by a considerable amount and which will be so simple that it is economical to produce and use.

It is also an object of my invention to provide a simple and efficient ejecting head which can be attached to and used with both mechanically-fed and air-fed rivet tubes with great facility.

A further object of my invention is to provide an improved type of rivet-ejecting head especially adapted for air-teed operation so that the speed of setting rivets is further increased. 7

Still another object of my invention is to provide a rivet-feeding tube which holds an unusually large number of rivets and which can be conveniently carried on the body of the riveter without in any way interfering with his various operations.

- By the use or rivet holding and-eiecting means such as shown herein, loose rivets are kept o-fi the floor and the is assured as the result of thorough testing, it has been demonstrated that the forms of my invention illustrated herein accomplish "the object heretofore stated as well as other objects and advantages which will become apparent from the following descriptlonof these forms of my invention,

use of rivets of the correct size taken 'withthe accompanying drawings, in which the head after the forward rivet has been elected and the next rivet has been moved into intermediate position,

Fig. '5 is an end elevation of the head of Fig. 4,

Fig. 6 is an enlarged perspective of the escapement mechanism employed in the head of Figs. 1 to 5,

Fig. 7 is a bottom plan view of the head,

Fig. 8 i a perspective utility view of .my im proved form of rivet-feeding coil adapted for compressed air feeds,

Fig. 9 is a side elevational view of a modified form of rivet-ejecting head adapted specifically for an air-operated feed, a

Fig. 10 is a vertical section of the mod-i-fi form of head taken on the line l0=l0 of Fig. .9,

Fig, 11 is a vertical side-elevational section of said head taken on the line I l'| of Fig. 1 0,

Fig, 12 is a vertical longitudinal section of still another form of my rivet-ejecting head which is suitable for use with both mechanical and :air

feeds,

Fig. 13 shows a modification of the form shown in Fig. 12' illustrating a difieren t style of cam operation, and

Fig. 14 is an end view of the modified form shown in Fig. 13. t

Referring now to the drawings and particularly to Figs. 1 to '7 thereof, the numeral 20 designates what I now consider to be my preferred form of rivet-ejecting h'ead suitable for both mechanical and air feeds. For mechanical feeding of the rivets, the head 20 may be attached to the end of a rivet-holding tube 2| provided with a plunger 22 actuated by a spring 23. The tube 2| is preferably provided with a hole 24 a. shortdistance from its rear end so that when the spring 23 is compressed into the space between the hole 24 and the rear end of the tube 2|, a pin such as arivet may be loosely inserted in the hole 24 to hold the spring in retracted position, thus allowing the tube 2| to be filled with rivets from its open forward end. The plunger 22 is preferably cylindrical in form and may be provided with an extending forward portion 25 of reduced diameter, which engages the head of the adjacent rivet and will also serve to indicate when the ejector is empty, as will be pointed out hereinafter.

The housing of the rivet-ejecting head Zllis preferably formed as a cylinder 26 having a bore 21 whose diameter is just slightly larger than the diameter of the heads of the rivets which are to pass through it. As a convenient means of attaching the head 20 to the rivet-holding tube 21, the rear end of the cylinder 26 may be internally threaded as shown at 28. The central 'portion of the housing is preferably enlarged. as at 29, to facilitate holding it in the hand, and the ;enlarged o recessed portions 40 and 49a.

upper portion of this enlargement is milled as indicated and then slotted on its upper face to form ears 3D and 3| which accommodate an op erating lever 32, which is pivotally mounted on a pin 33 passing across the slot in the ears. So that the forward end of the lever 32 will be continually urged downwardly towards the cylinder 26, a spring 34 is provided which may be seated in a hole 35 on the upper face of the cylinder 26 and arranged to engage the lower face of the rear portion of the lever 32. It is also desirable to supply'a stop to limit the movement of the lever 32, which stop can conveniently be in the form of a pin 36 depending from the lower face of the rearward portion of operating lever 32. When the parts are proportioned as illustrated in the drawings, the lever 32 will be in an approximately horizontal position at the end of its stroke.

The big problem in rivet-ejecting devices has always been that of accurately pointing the rivet so that it can be easily inserted in the hole without having to employ additional means at the point of ejection which hinder the removal of the ejecting head after the rivet has been placed in the hole. This problem has been completely overcome by the escapement means now to be described.

Adjacent the forward end of the cylinder 26, I bore a vertical hole through each of the side walls thereof, the holes being spaced so that the central portions thereof pass through the bore 21. These forward holes are designated in the drawings as 35 and 36a, it being seen that they are directly opposite each other on opposite sides of the bore. Similar holes 31 and 31a are bored a short distance back of holes 36-36:; and located in relatively the same position. Vertical rods 33 and 3311 are slidably mounted in the holes 36-36a, and rods 39-39a are slidably mounted in holes 31-3la. Each pair of rods is suspended from the forward end of the operating lever 32 with a pivotal connection which is preferably loose enough so that the rods may move in a true vertical path without binding, even though the forward end of the lever 32 moves in an arc. A very convenient way of making the pairs of rods 38 and 39 is to form them of fairly'heavy wire merely bent in the shape of a U. The U-shaped rods are then slipped through loose-fitting holes on the forward end of lever 32 and allowed to hang in a vertical position so that they may be moved up and down in their respective holes 36 and 31.

The rods 38-3811 are cut away or recessed on their inner faces adjacent their lower ends in that port on thereof which is aligned with the bore 21 when the rods are in their uppermost position as shown in Fig. 4. These recessed portions 43 and 40a can be conveniently made by first raising the rods to their upper position and then introducing a boring tool which is just the size of the bore 21, thus with one operation. producing the proper size, shape and position of the The rods 39 and 39a are similarly bored by introducing a drill from the rear end of the head when the rods are in the lowermost position as shown in Fig. 2 thus producing recessed portions 4l-4la which are oifset from recesses 40-4Ua as seen best in Fig. 6. It wiil thus be apparent that when the rivet-ejecting head is in normal inoperative position, i. e., when the lever 32 and its associated parts are in the position shown in Fig. 2. that the rods 38 and 38a provide a barrier in the bore 2! which restrains the rivets from passing therethrough and the cut-away portions 4l-4Ia of rods 39-39a are aligned with the bore and provide no barrier therein. It will also be seen that when the head is in the position shown in Fig. 4 that the rods 39-3911 have been raised to carry their recessed portions 4l-4la out of the bore 21 to thereby create a barrier therein, while the recessed portions 40-4311 of rods 33-3811 have been raised to alignment with the bore, thus removing the barrier previously formed by said rods.

In operating the rivet-ejecting head just described, it and the tube 2| are filled with rivets of an appropriate size, and the plunger 22 is released to urge the rivets forwardly. With the head loaded, a rivet 42 shown in Fig. 2 is ready for ejection and is held in this position by the tail of rivet 43 pressing against the head of rivet 42, all of the rivets being held together by reason of the spring 23. Depression of the rear end of lever 32 will raise the rods 38 and 39 as previously explained, thus bringing the recessed portions 40 and 48a in alignment with the bore 21, so that the pressure from the spring 23 transmitted through the line of rivets will forcibly eject the rivet 42 into its desired rivet hole if the head has been properly aligned therewith. However, in this position, i. e., the one shown in Fig. 4, it will be seen that the rear rods 39-3911 are in their barrier position so that as the second rivet 43 is forced outwardly, its head engages the rods 39-39a and is restrained from moving any further. When the lever 32 is released, the rods all move downwardly to their rest position which causes the rivet 43 to be released by rods 39-3912 and forced 40 the forwardly extending pin 2 5 of plunger 22 win project through both pairs of rods and the piston portion 22 will lock in the recessed portion of rods 39-39a, thus preventing operation of the lever 32 and signifying to the operator that the holder is empty, whereupon the head can be removed from the tube and the device can be refilled. It will be apparent that by placing the rods 38-38a fairly closejto rods 39-3911 that various lengths of rivets can be used in the same head without any modification thereof, which of course is a distinct advantage in that it cuts a down the number of heads required on a given job.

Referring now to that part of my invention illustrated in Fig. 8, it will be seen that I provide a relatively long tube, having a forward por-- tion 45 upon the free end of which is mounted a rivet-ejecting head of suitable design, such for example as the head 20 shown in Figs. 1 to 7, and having a coiled portion 46 adapted to be mounted on the body of the riveter in convenient manner as shown. The other end of the rivetholding tube is attached to an air-hose through a suitable valve 41 to regulate the air pressure therein. By coiling the rivet-holding tube, it is possible to provide space for a very large number of rivets without producing a bulky or unmanageable device, whereas if the tube were not coiled, it would be impossible to handle more than a very short length thereof. From a practical standpoint it is essential that the coil be in such form as will permit it to be mounted directly on the body as shown in Fig. 8 or fastened to the body or the clothing of the riveter by suitable means not shown. By coiling the tube and mounting it on the body, it becomes possible .for a person operate the rivet ejector with one hand ands. rivet "hammer with the other without either hindering the operation of the other.

Referring now to Fig. 9 wherein I show an eiector head that is practically fully automatic and on which is particularly suitable for rapid work and for use in combination with a coiled rivet-holding tube such as shown in Fig. 8, the numeral 51) indicates a housing having a horizontal boreSil in the upper portion thereof and of a size sufficient to pass rivets therethrougl'i. head 50 is adapted to be attached to the end of the rivet-holding tube 52 in alignment with the bore and provided with a suitable valve 53 to control the flow of air therethrough. The housing is provided with a vertical bore 54 terminating just below the horizontal bore 5|,

,in :which a piston 55 is slidably mounted. .An

angular passageway 56 connects the rearward portion of the bore 5| with the lower end of the cylinder 54, thus providing an air inlet for the said cylinder, while a passage 51] leads from the upper end of the cylinder 54 to the atmosphere, thus providing an air vent for the upper end of the cylinder.

upper wall of the head 50 above the bore 5| which I have indicated by the numeral 58 is pierced .by four holes which are drilled down through the bore and through the partition between the bore -5| and the bore 54, these four holes being arranged approximately in the .manner of the holes 36 and 3] shown in Fig. 7..

Two pairs of rods 60 and Gil are mounted on the forward or upper end of the piston 55 in alignment with the four holes just described and are of such length that when the piston 55 is in its retracted or rest position, as shown in Fig. 10 the upper free ends of the rods will be approximately flush with the top face 58 of the housing and when the piston is in its uppermost position, the rods will be in the position shown in Fig. 11, i. e, extending up beyond the face :58. The forward rods 60 are provided with recessed portions on their inner faces to make an opening the same size as the bore 5|, these recessed portions being indicated by the numerals 62, while rearward rods 61 are provided with similar recessed portions 63 offset from the portions 6'2. These recessed portions are positioned in the same man- 2 ner asthe recessed portions of the rods 3839, except that they are reversed, i. e., they are staggered so that when the rods are in their lowermost positions as shown in Fig. 10, the

recessed portions 62 are aligned with the bore 5| and when the rods are in their uppermost position, shown in Fig. 11, the recessed portions 63 arealigned with the bore 5| and the rods 69 are creating a barrier in the bore. It.will be seen that this is just the reverse of the arrangement shown in Figs. 1 to 6 so that the operation is also reversed. However, either system can be employed in either type of head, i. e., they are strictly interchangeable.

A spring 64 is cradled in the space formed between the rods 60- -6l in order to return the cylinder to its lowermost position, and a stop 65 which may be in the form of a shoulder in the cylinder 54 is provided to keep th rods from moving too far upward. Similarly, a stop 66 is provided at the lower end of the bore 54 so that when the piston 55 is in its retracted position, the recessedportions 62 of rods 60 will be aligned with the bore 50.

Referring now to Fig. 9, it will be seen that held in the bore by the rods 6|.

the :angularly positioned passage 56 is provided with an outlet passage 61, which vents passage55 to the-atmosphere. Consequently, when the head is connected to an air hose andthe valve opened, air will :pass down through the tube and into the horizontal bore '5], part of it passing out around the rivets and part of .it by-passing down through the air inlet 55 and hence to the atmosphere through the vent 61. Under these conditions, the spring 64 retains the piston 55 in its retracted position shown in Fig. 10, with a rivet being However, when the vent B 1 is closed as by placing ones finger overjit, suflicient air passes through the passageway 56 into the lower end of the cylinder "54 to raise the piston 55 upwardly, to the position shown in Fig. 11. This brings the recessed portions 53 of rod 61 into alignment with the bore 5| and releases the rivet .68, permitting it to be blown forwardly until its head engages the rods 50, which in this position provide a barrier to the exit of the rivet. As soon as the finger is removed from air vent 61, the air pressure in the lower end of cylinder 54 falls to atmospheric and allows the spring 64 to move the piston and rods back to their lowermost position, thus aligning therecessed portions 62 of rods 60 with the bore 5| and allowing the rivet '68 to be blown out .of the head and into its appropriate hole. As previously mentioned, the rods (ill and 6| may be interchanged so that when the air vent 61 is closed, the rivet will be blown out of the ejector and a new rivet loaded in place behind rod 65 when the air vent is again opened and the spring 64 comes into play.

it will be seen that this form of my invention provides a very rapid way of positioning rivets with a very simple mechanism, in which there is only one moving part. Furthermore, the effort expended by the riveter is reduced to a minimum, since he has no levers to operate nor valves to control, the whole operation being accomplished by simply placing his finger over a small hole and then removing it.

Referring now to Fig. 12 wherein I have shown another form of my invention which may be operated with either mechanical or air feeds, the numeral it! indicates a tubular head having a central bore I! through which rivets may pass in the manner previously explained. In this form of my invention, instead of utilizing slidable rods to provide the escapement mechanism, I employ two sets of movable members such for example as ball bearings, one set in back of the other, and each independently movable radially of the bore ll. Each set preferably employs a plurality of ball bearings, two being shown in Fig. 12.. The forward set comprises ball bearings l2 and 1211, each mounted in sockets 1'3 and 13a which extend through the walls of the tubular head 15 .and are provided with abutments to keep the walls from passing too far into the bore 1 The second set of ball bearings comprising balls 14 and 14a are seated in sockets i5 and 15a in a manner similar to the first set of ball bearings. The ball bearings are of such size that they can be easily forced outwardly or radially by pressure of the rivet head, so as to permit the rivets to pass through the bore 1| unless the balls are restrained in their innermost position.

To restrain the ball bearings alternately, I provide a longitudinally slidable cam 15 which is preferably cylindrical in shape and surrounds the tubular head 10 as indicated. The forward end of the inner face of the cam 15 is provided with an angular camming face 11; and a similar camming face 18 is provided adjacent the rear end of the cam on its inner surface. The camming faces T! and (8 are proportioned so that when the cam 16 is in its forwardmost position the balls 12 and 12a will be forced inwardly to create a barrier in the bore H and the balls I l-14a will be freely movable in their sockets 15-1541 so that they can be moved outwardly by a rivet head pressing on them.

With the head in the position shown in Fig. 12, the cam 16 is moved rearwardly against the force of a spring 19, which abuts against a wall 80 on the rear end of the head It, thus releasing the pressure on the balls 72-'l2a and allowing the rivet 88 to be ejected by reason of the force exerted on its head through the rivet 82. However, movement of the cam 16 rearwardly brings the camming face 18 into engagement with the balls IL-74a forcing them inwardly so that they provide a barrier to the movement of the rivet head 82, thus causing it to be restrained at that point. The cam collar 16 is then moved forwardly, permitting the rivet 82 to force the balls '|4'|4a outwardly and move forward until it is engaged by the balls ?2--12a which have again been forced inwardly. It will be seen that by the repetition of this cycle all of the rivets from a tube connected to the rear end of the head may be ejected consecutively as needed.

Since it is advantageous to have the rivets ejected by a forward hand movement, I also provide such a type of cam operation for the ballbearing form of my invention. This is illustrated in Figs, 13 and 14, wherein it will be seen that the numeral 90 designates a cylindrical housing having a bore 9! for the rivets to pass through. A forward set of radial sockets 92, in thi case three, is provided adjacent the forward end of the bore 9|, in which movable members such as balls 94 are loosely seated and adapted to restrain the first rivet 99 in the bore when they are held in their innermost position. A similar set of sockets 93 is formed to the rear of the first set and provided with balls 95 likewise adapted to be moved into and out of the bore 9| to alternately restrain and release rivet I90.

In this form of my invention I provide a cylindrical collar cam 96, having forward and rearward internal camming faces 9'! and 98 respectively, adapted to engage the forward and rearward sets of balls, respectively. A stop pin I92 may be screwed into the outer face of the housing 99 if desired, access thereto being had through a hole "ii in the cam 95. It will be evident that when the cam 95 is moved forwardly the forward set of balls 94 will be released and forced outwardly by the pressure exerted by the head of rivet 99, while the balls 95 will be held in rivet-restraining position by cam face 98, thus therethrough; a cylinder whose axis is substanpreventing rivet 00 from following rivet 99 out of the bore. After the rivet 99 has been ejected, the cam is moved rearwardly to release balls and lock balls 94 in restraining position, so that rivet I00 can move forward to a position ready for ejection, i. e., the position formerly held by rivet 99.

It is thus seen that I have provided several forms of my invention, all capable of attaining the objects and providing the advantages previously stated, but it is to be understood that these formsshown in detail herein are merely illustrative of my invention as defined by the appended claims.

I claim:

l. A rivet ejector adapted to be connected to a source of compressed air, which includes: a housing having a bore for the passage of rivets tially normal to that of said bore; a fluid passageway connecting the rear end of said cylinder to said source of compressed air, said passageway having a closable vent to the atmosphere; a piston slidable in said cylinder and adapted to be moved forwardly when said vent is closed; a pair or parallel rods on the forward end of said piston extending through the side walls of said bore and spaced so as to restrain the forward movement of the first rivet therein, said rods having opposed recessed portions on their inner faces spaced to pass the head of said rivet and adapted to be aligned with said bore when said piston is in one position; and means for moving said piston rearwardly when the pressure on its rear end is released, to move the rivet-engaging portions of said rod into said bore;

2. A rivet ejector, which includes: a housing having a rivet-holding bore adapted to be connected to a source of compressed air; a cylinder adjacent said bore having its axis substantially normal to that of said bore and adjacent its forward end; a piston slidable in said cylinder; two pairs ofparallel rods on the forward end of said piston, and extending laterally through said bore to restrain the first and second rivets therein respectively, each pair of rods having opposed recessed portions on their inner faces spaced to pass a rivet head, said recessed portions being located so that they are alternately aligned with said bore when said piston is reciprocated, whereby said rivets are alternately restrained and released; a fluid passage connecting the rear end of said cylinder with said air supply; valve means to cause air under pressure to flow into the rear end of cylinder to move said piston forwardly; and" a spring housed between said parallel rods adapted to return said piston to its rest position when the pressure behind saidpiston is released.

CLAGGETT OFFU'I'I.

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