US3695086A

US3695086A - Lockbolt swaging apparatus

Info

Publication number: US3695086A
Application number: US74254A
Authority: US
Inventors: Donald Stanley Savage
Original assignee: Aerpat AG
Current assignee: Aerpat AG
Priority date: 1969-09-26
Filing date: 1970-09-22
Publication date: 1972-10-03
Anticipated expiration: 1989-10-03
Also published as: ZA706362B; DE7035328U; FR2062737A5; JPS5011628B1; GB1328498A

Abstract

A device to facilitate the placing of lockbolt type fasteners by means of apparatus which swages a lockbolt collar onto the grooved stem of a lockbolt pin has a resilient body portion which frictionally grips the swaging apparatus so as to mount the device on the apparatus, and resilient arms which frictionally grip the collar to be swaged and hold it in appropriate relationship to the swaging apparatus to permit insertion of the stem through the collar and the swaging anvil of the swaging apparatus. The device may co-operate with a movable part of the swaging apparatus to produce movement of the arms to release the collar and to avoid interference of the device between the swaging apparatus and the work.

Description

United States Patent 1151 3,695,086 Savage 1 51 Oct 3, 1972 1 LOCKBOLT SWAGING APPARATUS Primary Examiner-Charles W. Lanham Assistant ExaminerGene P. Crosby I 9 b v [72] Inventor ds-tanley Savage A! ans AItOrner-Kemon, Palmer & Estabrook [73] Assignee: AerpatA.G., Zug, Switzerland 57 ABSTRACT Filedi p 22, 1970 A device to facilitate the placing of lockbolt type [21'] AppL No: 74,254 fasteners by means of apparatus which swages a lockbolt collar onto the grooved stem of a lockbolt pin has a resilient body portion which frictionally grips the [30] Apphcauo" Pnomy Data swaging apparatus so as to mount the device on the Sept. 26, 1969 Great Britain ..47,526/69 apparatus, and resilient arm which frictionally p v the collar to be swaged and hold it in appropriate rela- [52] US. Cl ..72/391, 227/149 tionship to the swaging apparatus to permit insertion. [51] Int. Cl. ..B21d 9/05 of the stem through the collar and the swaging anvil of [58] Field of Search ..72/391, 114; 227/149 the swaging apparatus. The device may co-operate with a movable part of the swaging apparatus to References Cited produce movement of the arms to release the collar UNITED STATES PATENTS 3,521,398 7/1970 Coutts ..227/149 477,241 6/1892 Bray .227/149 FOREIGN PATENTS OR APPL1cAT1oNs' 102,715 8/1963 Norway ..72 /391 and to avoid interference of the device between the swaging apparatus and the work.

12 Claims, 12 Drawing Figures PATENTEDnma m2 SHEET 2 [IF 3 N? R w. Q Q a,

MN QM,

V. r e I mm M w v PATENTED 3 3.695 O86 l n venlor LOCKBOLT SWAGING APPARATUS The invention relates to lockbolt-swaging apparatus, and also to an accessory for use with lockbolt-swaging apparatus.

By-flockbolt is meant a fastener of the type comprising a pin with a head at one end and one or more locking grooves on the stem of the pin at a position spaced from the head, and a collar which fits over the stem of the pin and which, in use of the fastener, is swaged into the aforesaid locking groove or grooves to lock it to the pin.

Such lockbolts are usually placed or set by means of lockbolt-swaging apparatus which comprises an annular anvil which swages the collar into the locking groove(s), and a retractable member carrying stemgripping means (eg jaws) which can grip a portion of the stem extending beyond the locking groove(s) when it is inserted through the annular anvil, retraction of the retractable member with respect to the anvil when the stem-gripping means are gripping the stem of a pin as aforesaid causing the anvil to swage the collar into the locking groove(s).

Such lockbolt-swaging apparatus is hereinafter referred to as lockbolt-swaging apparatus of the type defined."

Such lockbolts, and such lockbolt-swaging apparatus, are well known and are well understood by those skilled in the art of industrial fasteners.

The invention provides, in one of its aspects, a collarcarrying device for attachment to lockbolt-swaging apparatus of the type defined, which collar-carrying device is adapted, when attached to the lockbolt-swaging apparatus, to retain a collar in appropriate relationship to the annular anvil while the stem is inserted through the collar and the annular anvil.

Preferably the device is arranged to release thecollar after the start'of, and before the completion of, swaging of the collar to the pin stem.

When the device is such that part of it, when in use and retaining a collar as aforesaid, masks or overlies the portion of the annular anvil axially nearest the head of the pin, then preferably the device is arranged so that the said part of it is removed from its masking or overlying position before the completion of the swaging of the collar to the pin stem by movement of ,the said part transversely of the pin stem, so that the said part of it is not trapped between the said portion of the annular anvil and the adjacent face of a workpiece in which the lockbolt has been placed, when the anvil has completely swaged the collar to the pin stem.

Preferably the device is such that the transverse. movement of the said part is effected by relative axial movement of the device and at least part of the swaging apparatus, at least one of these having at least one inclined surface to convert the axial movement to transverse movement of the said part of the device.

Preferably the or each inclined surface is provided on.

the device. Preferably the said part of the swaging apparatus is the anvil. Preferably relative axial movement of the device and the anvil is provided by the abutting of the device with the aforesaid adjacent face of the workpiece, before the anvil has completely swaged the collar to the pin stem. Preferably return relative movement of the device and return of the said part of the device to the masking position is provided by return member.

In a preferred :embodiment of the invention, the device comprises a plurality of opposed arms. Preferably one extremity of each arm contacts the collar. Preferably the other extremity of each arm is secured to or integral with a body portion of the device which is secured to the swaging apparatus. Preferably the arms are resiliently urged together to grip the collar. Preferably the body portion of the device resiliently grips the swaging apparatus. Preferably the device is a unitary structure of resilient material, e.g. spring steel.

The invention includes the combination of lockboltswaging apparatus of the type defined with a collar-carrying device as aforesaid.

A specific embodiment of the invention will now be described by way of example and with reference to the accompanying drawings, in which:

FIG. 1 is an end elevation of a collar-carrying device according to the invention;

FIG. 2 is a plan of the device;

FIG. 3 is a side elevation of the device;

FIG. 4 is a section on the line-IV-IVof FIG. 2;

FIG. 5 is a view of the device attached to the nosepiece of a lockbolt-swaging tool;

FIGS. 6, 8, l0 and 12 are axial sections through the nosepiece and device in use, showing successive stages in the swaging of a collar onto a pin stem;

FIG. 7 is an end elevation taken in the direction of the arrow VII in FIG. 6;

FIG. 9 is a section on the line IXIX of FIG. 8; and

FIG. 11 is a section on the line XI-XI of FIG. 10.

The lockbolt shown in FIGS. 6-12 is of a well-known type available commercially under the trade mark AVDELOCK and comprises a pin 1 l and a collar. 12. The pin 11 comprises a stem having a head 13 at one end. Adjacent to the head the stem has a length 14 of plain exterior (chosen to correspond approximately to the total thickness of the workpieces to be joined), and

then a plurality ofcircumferential swaging grooves 15 into which the collar will be swaged. Beyond the swaging grooves is a breaker groove 16, and beyond this are gripping grooves 17 which are engageable by the gripping means on the retractable member of the lockbolt-swaging apparatus.

The collar 12 comprises a cylindrical exterior portion 12a, joined by a shoulder 120 to an enlarged exterior portion 12b which tapers away from the cylindrical portion and towards the end of the collar, that end being chamfered to be received within the end of the throat of the anvil as illustrated in FIG. 6. The interior of the collar is of plain cylindrical form of sufficient diameter to be a clearance over the exterior of the stem of the pin.

The lockbolt-swaging apparatus of this example is provided by a well-known form of lockbolt-swaging tool, of which only part of the nosepiece is illustrated in the accompanying drawings. The nosepiece of the tool comprises an annular anvil 18 formed at one end of an outer tube 19 secured to the head member of a hydraulic tool (not shown). The anvil has an annular end face 20 (which in use is the part of the anvil nearest to the head of the lockbolt) and a throat 21 of tapering form, the annular face 20 surrounding the outer end or mouth of the throat. The retractable member is providedin the-form of a-tubular drawbolt 24 which is disposed within the tube 19 and secured to the pulling member of the hydraulic tool. The gripping means comprises a pair of collet jaws 22, the inner faces being serrated to engagewith the gripping grooves 17 on the pin, stern and the outer faces being tapered and received within the tapering inner walls 23 of the end of the drawbolt 24. The jaws are urged into the collet taper by means of a spring (not shown) actingthrough a back-up member 30 in the bore of the drawbolt.

The standard nosepiece illustrated in the accompanying drawings has two diametrically opposed parallel flats 31 ground at its extremity, in order to enable .the nosepiece to be inserted into narrow gaps to place lar to the bolt, without the use of .the collar-carrying device of the present invention, the pin is inserted through aligned apertures 25 in sheets 26 of metal to be fastened together and the collar 12 is placed over the locking grooves 15 on the projecting part of the stem. The tool is then offered up to the stem so that the end of the stern enters between the jaws 22 and is gripped by them, and the outermost end of the anvil throat 21 adjacent its mouth contacts the end of the collar (this position would be as illustrated in FIG. 8, the collarcarrying device being omitted). The hydraulic tool is then actuated, retracting thedrawbolt 24 relative to the tube 19 and anvil 18. The jaws 22 pull the pin so that the head 13 is pressed tightly against one face of the workpieces and the collar 12 is pushed tightly against the other face of the workpieces. The sheets 26 support this compression, and as the inward pull on the jaws 22 with respect to the anvil increases, the consequent increasing compression of the collar between the face of the sheets at one end and the tapering anvil throat at the other end causes the collar to deform. The tapered anvil throat passes down over the outside of the collar, swaging it inwardly into the locking grooves 15 on the stem.\Vhen the end face of the anvil reaches the face of the workpieces it stops since the sheets support the compression between the head 13 of the bolt stem and the face 20 of the anvil, but the tension on the pin stem continues to increase due to the action of the hydraulic too], until the stem breaks at the breaker groove 16. The hydraulic tool is then actuated to return the drawbolt 24 to its original position with respect to the anvil, so that the push off nose 24a provided at the front end of the drawbolt contacts the rear face of the swaged collar and pushes the anvil off the swaged collar. Such a lockbolt and the method of placing it with a swaging tool as has been described above are well known to those skilled in the art.

The collar carrying device illustrated in the accompanying drawings and more particularly in FIGS. 1-5 thereof is arranged to fit over the nosepiece of the swaging tool to releasably carry a collar adjacent the anvil in the appropriate position for placing the collar and the anvil over the lockbolt pin stem. It will be seen from FIGS. 1-5 that the device, which is made of spring '35 which lie in contact with the flats 31 of the nosepiece. In the middle of each flat wall section 35 there is a dimple 36 which projects inwardly through the slot 32in the nosepiece and into the annular space surrounding the annular push off nose 24a in front of the annular end face 37 of the front end of the drawbolt. The four arms 34 which extend forwardly from the flat-wall section 35 of the body portion of the device are provided in two pairs of adjacent arms. One pair is provided by a bifurcated tab 38 with a central slot 39 extending along most of its length, and the otheropposite pair of arms is provided by a similar tab 41 having a central slot 42 (these reference numerals are indicated in FIG. 5). The major part of the length of each arm is inclined to the axis of the body portion to provide an inclined surface 43. The remaining part 44, at the free end of each arm, extends towards and perpendicular to the axis of the body portion and is provided with an arcuate collar-gripping portion 45, the four arcuate portions 45 of the four arms lying on the circumference of a circle which, in the undeformed position of the resilient arms is of slightly smaller diameter than the external diameter of the cylindrical portion 12a of the collar. Each portion 45 tapers to a narrow arcuate edge 46 which actually contacts the collar.

In 'use, the device is attached to the nosepiece of the tool as already described and illustrated in FIG. 5 (which shows the device without a collar inserted between its arms). The device is mounted on the tool nosepiece by springing the body portion apart until the distance between the dimples 36 is sufficient to pass over the outside end of the anvil across the flats 31. The dimples drop into the slots 32 and the body portion of the device grips the exterioriof the outer tube, but can be slid axially along the outer tube to a limited extent, provided that sufficient force is applied to overcome the frictional grip of the device on the outer tube. It will be seen that the arms 43 extend outside and around the anvil with their collar gripping portions in front of the anvil and the imaginary circle on which the four part circular gripping portions 45 lie being concentric with the axis of the annular anvil.

A collar 12 is then inserted into the device by pushing the tapered end 12b of the collar into the device, the tapered surface 12b pushing the arms slightly apart until they drop over the shoulder between tapered portion 12b and the cylindrical portion.l2a and grip the collar by the portion 120. The collar is pushed home until the narrow end of its tapered portion 12b contacts the outer end of the anvil throat, as illustrated in FIG. 6. in this position, the collar is retained by the device and supported sufficiently securely that the nosepiece of the gun, carrying the collar, can be pointed in any direction without the collar moving relative to the anvil. The tool nosepiece, together with the collar, is then offered up .over the-end of the pin stern and pushed over the pin stem until the end face of the collar abuts the adjacent face of'theworkpiece. This position is il- 'towards the head of the lockbolt, but the anvil 18 continues to move in that direction. Accordingly the front end of the anvil engages with the-inclined surfaces 43 of the arms and forces the arms outwardly against their own resilience, thus releasing the collar from the grip of the arms. This outward movement of the arms continues until the front annular face 20 of the anvil reaches the adjacent face of the workpieces, as illustrated in FIG..10. It will be noted from FIGS. and l I that, when this occurs, the free end parts 44 of the arms have been moved from the position in which they masked the annular end face 20 of the anvil, so that they are not trapped between this end face and the adjacent face of the workpieces.

It will be noted from FIG. 10 that the device has moved rearwardly along the outer tube 19 until its rear end has nearly reached the rear end of the flats 31. The drawbolt 24 has of course also retracted, so that the dimples 36 onthe body portion of the device have not been obstructed by the annular face 37 of the drawbolt. After the pin stem has fractured at the breaker groove and when the drawbolt starts its return movement, the push off nose 24a on the drawbolt contacts the rear end of the swaged collar to push the anvil off the swaged collar, as previously described. After the ,front end of the push off nose 24a has contacted the rear endof the swaged collar and has started to pull, the anvil off, the advancing annular face 37 on the drawbolt meets the dimples 36 on the body portion of the device and starts to push the device axially forwards again along the nosepiece. This allows the arms to close progressively inwardly again, which they are able to do since the anvil is being withdrawn from contact with the adjacent face of the workpieces. As they close,,the parts 45 of the arms may skate along the exterior surface of the swaged collar. When the drawbolt has completed its return movement the nosepiece and the collar-carrying device return to.their original position, as illustrated in FIG. 12.

It will be noted that the construction andoperation of the device ensures that the gripping portions of the arms do not-release the collar until after swaging of the collar to the pin stem has commenced, and that this release, and the removal of the extremities of the arms from between the annular end face 20 of the anvil and the adjacent face of the workpieces, is completed before the completion of swaging and the arrival of the end face 20 of the anvil at the adjacent face of the workpieces.

The collar-carrying device of this example enables collars to be successfully positioned and swaged onto lockbolts in positions which otherwise would not be possible, e.g. in a position with a lockbolt pin stem pointing downwards and positioned at arms length above an operator, when there would be no other convenient way of placing the lockbolt on the pin stem and holding it in position during the application of the tool.

.I claim:

1. A collar-carrying device comprising a body portion for attaching the device to lockbolt-swaging apparatus of the type defined, and a plurality of arms extending forwardly of the body for holding a collar for a lockbolt in front of an annular anvil of the swaging apparatus in appropriate relationship to permit insertion of a lockbolt stem through the collar and the annular anvil, said arms providing inclined surfaces for translat ing relative axial movement of the device and a part of the swaging apparatus into transverse movement of the arms.

2. Lockbolt-swaging apparatus of the kind defined comprising an annular anvil for swaging a lockbolt collar to a stem of a lockbolt pin, and retractable stem gripping means including a collar-carrying device comprising a body portion for attaching the device to lockbolt-swaging apparatus, and a plurality of arms extending forwardly of the body for holding a collar for a lockbolt in front'on the anvil of the swaging apparatus in appropriate relationship to permit insertion of a lockbolt stem through the collar and the annular anvil,

- said arms providing inclined surfaces for translating relative axial movement of the device and a part of the swaging apparatus into transverse movement of the arms. i 3. Lockbolt-swaging apparatus according to claim 2 wherein the collar-carrying device is axially movable relative to the annular anvil, the arrangement being such that, relative movement between the collar-carrying device and the anvil during swaging of a lockbolt collar causes transverse movement of the arms in a direction to release the collar being swaged.

.4. A device according to claim 1, wherein the arms are resilient.

5. A device according to claim 1, wherein the arms each comprise a first portion adjoining thebody portion of the device, and a free end portion, said free end portions being directed inwardly and generally towards each other.

6. A device according to claim 5, wherein the said first portions of the arms provide said inclined surfaces.

- 7. A device according to claim 1, wherein the body portion comprises means for resiliently gripping the swaging apparatus.

8. A device adapted to be mounted on lockboltswaging apparatus of the type defined and to hold a collar for a lockbolt in appropriate relationship to the annular anvil of the swaging apparatus to permit the lockbolt stem to be inserted axially through the collar and the annular anvil, said device comprising of a resilient longitudinally split tubular body portion for gripping the swaging apparatus and, integral with the body portion, resilient opposing arms which extend from one end of the body portion.

9. A device according to claim 8, wherein each arm comprises a first portion adjoining said body portion and a free end portion remote from the body portion, said free end portions being directed inwardly and generally towards each other and terminating at points lying on a circle, whereby said free end portions may resiliently grip the periphery-of the, lockbolt collar.

arms resiliently grip the collar.

l2. Lockbolt-swaging apparatus according to claim 2, wherein return relative movement of the anvil and the retractable stem gripping means produces return movement of the collar-carrying device relative to the anvil thereby to restore the collar-carrying device to a condition for retaining a collar.

* I I i

Claims

1. A collar-carrying device comprising a body portion for attaching the device to lockbolt-swaging apparatus of the type defined, and a plurality of arms extending forwardly of the body for holding a collar for a lockbolt in front of an annular anvil of the swaging apparatus in appropriate relationship to permit insertion of a lockbolt stem through the collar and the annular anvil, said arms providing inclined surfaces for translating relative axial movement of the device and a part of the swaging apparatus into transverse movement of the arms.

2. Lockbolt-swaging apparatus of the kind defined comprising an annular anvil for swaging a lockbolt collar to a stem of a lockbolt pin, and retractable stem gripping means including a collar-carrying device comprising a body portion for attaching the device to lockbolt-swaging apparatus, and a plurality of arms extending forwardly of the body for holding a collar for a lockbolt in front on the anvil of the swaging apparatus in appropriate relationship to permit insertion of a lockbolt stem through the collar and the annular anvil, said arms providing inclined surfaces for translating relative axial movement of the device and a part of the swaging apparatus into transverse movement of the arms.

3. Lockbolt-swaging apparatus according to claim 2 wherein the collar-carrying device is axially movable relative to the annular anvil, the arrangement being such that, relative movement between the collar-carrying device and the anvil during swaging of a lockbolt collar causes transverse movement of the arms in a direction to release the collaR being swaged.

4. A device according to claim 1, wherein the arms are resilient.

5. A device according to claim 1, wherein the arms each comprise a first portion adjoining the body portion of the device, and a free end portion, said free end portions being directed inwardly and generally towards each other.

7. A device according to claim 1, wherein the body portion comprises means for resiliently gripping the swaging apparatus.

8. A device adapted to be mounted on lockbolt-swaging apparatus of the type defined and to hold a collar for a lockbolt in appropriate relationship to the annular anvil of the swaging apparatus to permit the lockbolt stem to be inserted axially through the collar and the annular anvil, said device comprising of a resilient longitudinally split tubular body portion for gripping the swaging apparatus and, integral with the body portion, resilient opposing arms which extend from one end of the body portion.

9. A device according to claim 8, wherein each arm comprises a first portion adjoining said body portion and a free end portion remote from the body portion, said free end portions being directed inwardly and generally towards each other and terminating at points lying on a circle, whereby said free end portions may resiliently grip the periphery of the lockbolt collar.

10. A device according to claim 9, wherein said first portions of the arms are inwardly inclined, thereby to co-operate with the anvil of a swaging apparatus when said anvil moves forwardly relative to the device, to force said arms resiliently outwards and so to release a collar engaged between said free end portions of the arms.

11. Apparatus according to claim 2, wherein the arms resiliently grip the collar.

12. Lockbolt-swaging apparatus according to claim 2, wherein return relative movement of the anvil and the retractable stem gripping means produces return movement of the collar-carrying device relative to the anvil thereby to restore the collar-carrying device to a condition for retaining a collar.