GB2147841A - Combined drill/riveter - Google Patents

Abstract

Blind riveting apparatus includes a drill 54 which reciprocates in a cylinder, a nose assembly 26 which fixes the rivet in the workpiece and a rivet magazine 50 which pivots about an axis 52. The nose assembly includes a passage which allows the drill to pass therethrough in order to drill a hole in the workpiece. On retraction of the drill the rivet magazine is pivoted into place and a rivet is supplied to the nose assembly. The rivet is then inserted in the hole and the rivet mandrel pulled through to fix the rivet in place. <IMAGE>

Description

SPECIFICATION Improved fastening apparatus The present invention relates to fastening apparatus, with which two or more sheet members may be fastened together. The sheet members may have mating curved form.

More specifically the fastening apparatus is of the kind which fastens two or more sheet members together by riveting.

The invention will now be described by way of example with reference to the accompanying drawings in which: Figure 1 is a pictorial view of the apparatus.

Figure la is a cross sectional part view of the left hand portion of Figure 1 as viewed in Figure 1.

Figure 2 is a part cross sectional side view of the apparatus of Figure 1.

Figure 3 is a re-orientated cross sectional part view of Figure 2.

Figure 4 is a view in the direction of arrow 4 in Figure 2.

Figure 5 is a cross sectional part view of the apparatus of Figure 1.

Figures 6 to 8 correspond to Figure 5 in different stages of operation.

Figure 9 is an enlarged, cross sectional part view of the apparatus of Figure 1.

Figure 10 is a schematic view of the apparatus of Figure 1 and includes the hydraulic, electrical and pneumatic circutry therefor.

In Figure 1 a cylinder 10 and a cylinder 12 are held in fixed side by side relationship between a pair of end plates 14 and 16. Cylinder 10 contains a piston (not shown) which is movable on application of a hydraulic force.

The piston (not shown) has a rod 18 fastened to one end, which rod 18 projects through the end plate 16 and is fastened via its outer extremity to a further plate 20.

A drill and air motor for driving the drill and neither of which are shown in Figure 1, are slidably mounted in the cylinder 12 and a rod 22 projects from the end of the casing of the air motor, (not shown in Figure 1) in parallel with the rod 18. The rod 22 is fixed via its end to the further plate 20.

Thus, whichever way the piston (not shown) moves in its cylinder 10, the drill and airmotor (not shown) will move simultaneously and in the same direction, by virtue of their connection with the piston (not shown) via rod 18, plate 20 and rod 22.

In operation, the drill (not shown) will be required to move a given distance i.e. sufficient to pass through an assembly of workpieces (not shown in Figure 1). A stop mechanism is therefor provided, in the form of a bar 24. On the drill (not shown) achieving its maximum desired movement, the bar 24 which moves with the plate 20 to which it is fastened, into contact with a piston movement reversing device (not shown in Figure 1) on the plate 16, whereupon the piston (not shown) and therefor the drill (not shown) is caused to move in the opposite direction.

A cylindrical nose assembly, generally indicated by the numberal 26, is fastened to the outer face of the end plate 14, in coaxial alignment with the cylinder 12. The assembly 26 includes a pair of jaws 28 and 30 which are movable towards and away from each other, between guides 32 and 34. The two jaws 28 and 30 when pressed together, form a passageway 36 which is so proportioned as to grip the shank of a rivet which is not shown in Figure 1 but which will be described later in this specification.

A pair of conduits of which only the connecting ends 38 and 40 are shown, are provided so as to enable removal of drill swarffromthe nose assembly 26, by means of suction.

Two hand grips 42 and 44 are provided and hand grip 44 includes a trigger button 46, pressing of which will activate the apparatus.

Hand grip 46 is mounted on a rectangular bracket 48 which in turn is fixed to the cylinder 12. A rivet delivery pipe 50 lies within the bracket 48 and is pivotally mounted thereto, for arcuate movement about an axis 52 as will be described later in this specification.

Referring now to Figure 2. The drill and air motor, now shown and indicated by the numerals 54 and 56 respectively, are shown retracted and the pipe 50 pivoted through a slot 58 in the wall of the cylinder 12, into the position in which, in operation of the apparatus, it delivers a rivet not shown in Figure 2) to the nose assembly 26.

The further plate 20 supports a disc 60 for relative rotation about an axis coincident with the axis of the drill 54. A solenoid 62 is fixed to the plate 20 and connected to rotate the disc 60 through a fixed angle at a specific point in the operation of the apparatus, by means of a link 64. Push rods 66 pass through further plate 20 and in a first relative position, through disc 60 in close sliding engagement, so that when the further plate 20 moves the disc 60 the drill 54 and air motor 56 to achieve drilling of a workpiece, the push rods 66 remain in their positions.

Referring now to Figure 3. The push rods 66 have a reduced portion 68 and the disc 60 has arcuate slots 70 so proportioned as to closely fit the reduced portion 68 of the push rods 66. Thus, rotation of the disc 60 will bring the upper and lower surfaces of the disc 60 into engagement with the sides of the reduced portions 68 in the push rods 66. In this relative position, when the plate 20 and the disc 60 move as described hereinbefore, the push rods 66 will be caused to move also, in a common direction.

In Figure 4, the push rods 66 are shown extending to connect with the nose assembly 26 for reasons to be described hereinafter.

Referring back to Figure 1. The nose assembly 26 has a first sleeve 70 in coaxial, spigoted engagement with a second sleeve 72. The two sleeves are spaced axially by diametricaly opposed local radial inserts 74 (see Figure 9) carried by hollow blocks 76 (Figures 1 and 9).

The two sleeves 70 and 72 are initially maintained in a fixed axial relationship by further diametrically opposed features consisting of axially opposing hollow blocks 78 and 80 having a through bolt 82 and a compression spring 84, all of which are shown in Figure la.

Referring now to Figure 5. The nose assembly also includes an inner sleeve 86 which is attached to the ends of the push rods 66 (not shown in Figure 5). A pair of elongate abutments 88 are also attached to the inner sleeve 86 although this attachment is not shown. The inner sleeve 86 also carries a pair of jaws 87. The operation of the apparatus will now be described with reference to Figures 5 to 8. The apparatus is held against a workpiece 90 and the jaws 28,30 are opened and the drill 54 is moved as described hereinbefore, through the resulting gap and bores a hole through the workpiece 90.

In Figure 6, the drill 54 has been retracted again and the jaws 28 and 30 closed.

The rivet delivery pipe 50 has been pivoted through the slot 58 in the cylinder 12 and a rivet 94 delivered to the nose assembly 26.

The rivet is of the type known as a "Cherrylock" rivet. It is hollow and has a mandrel 96 through it, which projects to the right as viewed in the drawing.

The end of the mandrel 96 remote from the projection has a small head 98 which is deformable.

Referring now to Figure 7. The disc 60 of Figure 1 has been rotated so as to engage the push rods 66 as described with reference to Figure 3. The piston (not shown) has been actuated to move the further plate 20, disc 60 and thereforthe pushrods 66 to the left as viewed both in Figure 1 and in Figure 7. The movement causes both the inner sleeve 86 and the abutments 88 to move in the same direction. The pair of jaws 87 which are pivotally connected to the inner sleeve, are moved clear of sleeve 72 and swing inwardly into the mandrel 96 and push it through the hole 99 in workpiece 90. The jaws 28,30 are then closed. The axial movement is continued until the jaws 87 abut projections 100 on the inner end of the sleeve 72, which causes the jaws 87 to grip the mandrel more tightly.

The force applied to the piston (not shown) is reversed with the result that the movement of the push rods 66 and therefor the inner sleeve 86 is also reversed. The jaws 87 now pull the mandrel 96 to the right as viewed in the drawings. The rivet 94 cannot withdraw however, because the closed jaws 28 and 30 of the nose assembly 26 prevent such a move.

Consequently as the mandrel 96 moves through the rivet shank, the small head 98 on the mandrel 96 deforms (see Figure 7) into a normal rivet head shape. The workpiece 90 which in the example consists of sheets 90a and 90b, is thus riveted.

The movement of the sleeve 86 and associated jaws 87 to the right as viewed in the drawings, also moves abutments 88 in the same direction. Referring to Figure 8, it can be seen that the abutments 88 in their movement, engage the outer portions of inserts 74 and lift them radially outwards against the action of leaf springs 102. The sleeve 70 is then free to move to the right as viewed in the drawing, against the compression springs 84 (Figure 1 a) and this occurs when the operator exerts pressure via the apparatus on the workpiece 90. The closed jaws 28, 30 move however, with the result that the head of the rivet, 94 receives all of the pressure exerted via the apparatus, by the operator. The head of the rivet 94 is thus deformed against the workpiece 90. This thus deformed against the workpiece 90.This means that the two sheets 90a, 90b are effectively riveted from both sides, thus providing a much higherjoin than is normally achieved when known methods of riveting are utilised.

The piston and therefor sleeve 86 continues to move to the right until tensile sufficient force is exerted by jaws 87 on the mandrel 96, to break the mandrel 96 adjacent the head of the rivet 94. On the sleeve 86 having moved far enough for the outer ends of the jaws 87 to engage abutments 104 in sleeve 87, the jaws 87 pivot outwardly, releasing the mandrel, which drops out of the apparatus through a convenient slot.

On removal of the apparatus bodily from contact with the workpiece 90, the compression springs 84 separate sleeves 70 and 72 and the leaf springs 102 push the inserts radially inwards in the resulting gap, to make the apparatus ready for starting the next drilling/riveting sequence at another plate on the workpiece.

In Figure 10 the electrical, hydraulic and pneumatic circuitry needed to achieve operation of the apparatus, is depicted in schematic form.

Claims (10)

1. For use in the operation of riveting wherein a mandrel mounted rivet is inserted through an assembly of workpieces to be fixed together and the mandrel is thereafter retracted through the rivet to deform the rivet end against the underside of the assembly of workpieces and thereafter broken off, apparatus comprising a cylinder containing a drill and drill driving means in sliding relationship therein, means affixed to and externally of said cylinder and connected to move the drill in reciprocatory manner, a nose assembly at an end of said cylinder and including first jaws which are operable so as to enable in use, passage of said drill therethrough for drilling an assembly of workpieces and, on retraction of said drill, a rivetforfixing a said assembly, a tubular rivet magazine pivotally fixed to a side of said cylinder for pivoting to a position from which in said operation a rivet can be placed and inserted via said jaws, into the assembly of workpieces and means in the nose assembly for gripping the mandrel of a rivet so placed, achieving said insertion followed by retraction and breaking off of the mandrel.

2. Apparatus as claimed in claim 1 wherein the means for moving the drill comprises a piston slidably mounted in a cylinder and connected to the drill via a piston rod and a further rod coaxially aligned with and effectively connected to the drill, the piston rod and further rod each having ends affixed to a common plate via which the drill moving force is transmitted.

3. Apparatus as claimed in claim 2 wherein the piston cylinder and the drill cylinder are rigidly connected by end plates, movement of the piston and drill being relative thereto.

4. Apparatus as claimed in any previous claim wherein the means for gripping the mandrel comprises further jaws which are pivotally mounted to and internally of a first sleeve which is slidably mounted in the nose assembly.

5. Apparatus as claimed in claim 4 wherein said common plate has a disc mounted thereon for rotary movement about the axis of the drill, and push rods having ends projecting through both common plate and disc and extending therefrom parallel with and adjacent to the drill cylinder, said disc including arcuate slots and said push rod ends being adapted so as to engage within the ends of said slots or pass therethrough, depending on the position of said disc relative to said push rod ends, and wherein said extension is sufficient as to enable the push rods other ends to engage the sleeve which supports said further jaws for translation thereof, on axial movement of said push rods.

6. Apparatus as claimed in claim 5 wherein the nose assembly includes a pair of further sleeves arranged in coaxial, spigoted engagement such as to enable limited relative axial movement therebetween, said further sleeves being axially spaced by resilient means and radially movable wedges and wherein said first sleeve is slidably mounted therein.

7. Apparatus as claimed in claim 6 wherein movement of the pair of sleeves together exposes the extremities of the first jaws so enabling during operation, operator applied pressure to be concentrated via said extremities, onto a rivet head.

8. Apparatus as claimed in claim 6 or claim 7 including abutments movable axially of the apparatus to engage said wedges and move them radially outwards of the nose assembly so as to enable said limited relative movement of the pair of sleeves, to expose the extremities of said first jaws.

9. Apparatus as claimed in any previous claim including electrical, hydraulic and pneumatic circuitry for operation of said apparatus, substantially as disclosed in Figure 10 of the drawings.

10. Apparatus substantially as described in this specification and with reference to the accompanying drawings.