GB2306368A

GB2306368A - Rivet setting tool

Info

Publication number: GB2306368A
Application number: GB9622597A
Authority: GB
Inventors: Andreas Roessler
Original assignee: Newfrey LLC
Current assignee: Newfrey LLC
Priority date: 1995-10-31
Filing date: 1996-10-30
Publication date: 1997-05-07
Anticipated expiration: 2016-10-30
Also published as: GB9622597D0; GB2306368B

Abstract

A tool for setting blind rivets of the tubular type having a head 4, an internally threaded portion, and a screw-type mandrel having a pulling head 10, comprises a nosepiece, and a pulling assembly mounted in the nosepiece including collet members 101 for latching behind the mandrel head 10. An abutment assembly also mounted on the nosepiece includes a plurality of abutment members 54 that move between an open position through which the pulling head 10 of the mandrel may be passed to be subsequently engaged by the pulling assembly and a closed position in which the abutment members 54 engage the rivet head 4. Further included is a rod member 103 having a cam surface for opening the collet members 101 to release the mandrel head 10 after the rivet has been set and the pulling assembly has been released.

Description

RIVET BETTING TOOL The present invention relates to a riveting tool for use in setting blind rivets of the type which comprise a tubular rivet having a head, an internal screw thread and a mandrel which passes through the tubular rivet. The mandrel comprises a screw engaged with the thread in the tube and includes a head which can be pulled to move the mandrel relative to the rivet to set it. Such a device is described in U.S. Patent No. 5,403,135.

A tool for setting such a rivet requires a nosepiece supporting a pulling assembly adapted to grip the pulling head of the screw to pull the rivet and set it, and an abutment assembly arranged to engage the head of the rivet during its setting. It is necessary that the abutment assembly be capable of moving into an open position to allow the head of the screw past the abutment assembly to engage the pulling assembly, then into a closed position to provide an abutment to engage the head of the rivet and subsequently to open to allow the tool to be lifted away from the rivet while leaving the screw-mandrel engaged with the thread in the rivet body.

A known riveting tool intended for use with rivets of the type in which a double-headed mandrel is pulled to set the rivet and then broken and discarded is described in U.S.

Patent No. 5,337,463. The tool disclosed therein includes a nosepiece, a pulling assembly mounted in the nosepiece arranged to grip the pulling head of a mandrel to pull the mandrel to set the rivet. Further included is an abutment assembly mounted on the nosepiece and arranged to engage the head of the rivet during its setting. The abutment assembly comprises a plurality of abutment members extending generally axially of the nosepiece around the pulling assembly which are movable between an open position in which the pulling head of the mandrel may be passed through the abutment assembly to be engaged by the pulling assembly and a closed position in which the abutment members provide an abutment to engage the head of the rivet head.The abutment members are mounted for generally axial movement relative to the nosepiece against a spring bias and comprise cam means which, upon such axial movement, cause the abutment members to move from their open to their closed positions. The pulling assembly comprises a collet assembly including collet members having latches adapted to engage behind the head of the mandrel.

When a blind rivet is presented axially to this tool, the head of the rivet engages the abutment members and is pushed into the tool so that the pulling head of the mandrel is engaged by the latches of the collet members, the abutment members having moved axially relative to the nosepiece to move from their open to their closed position firmly about the mandrel.

This construction, however, is not suitable when the collet members must be reopened after the setting operation thereby to release the head of the screw-mandrel which is to be left behind in the rivet.

It is an object of the present invention to provide a riveting tool for use with rivets which include reusable screw-type mandrels, in which the above disadvantages are reduced or substantially obviated.

The present invention provides a riveting tool for setting a tubular rivet having a body, a head and a mandrel in the body having a pulling head to move the mandrel relative to the rivet body to set the rivet, the mandrel remaining in the body after the tool is removed, the tool comprising a nosepiece a pulling assembly mounted in the nosepiece and arranged to grip the pulling head of the mandrel and being movable relative to the nosepiece to pull the mandrel to set the rivet, the pulling assembly including collet members for latching behind the mandrel head, an abutment assembly mounted on the nosepiece and arranged to engage the head of the rivet body during the setting of the rivet and comprising a plurality of abutment members extending generally axially of the nosepiece around the pulling assembly and movable axially between an open position in which the pulling head of the mandrel may be passed through the abutment assembly to be subsequently engaged by the pulling assembly and a closed position, in which the abutment members provide an abutment engaging the rivet head, and a rod member having a cam surface for opening the collet members to release the mandrel head after the rivet has been set and the pulling assembly has been released.

The invention will now be further described with reference to the (accompanying) drawings, in which; Figure 1 is schematic cross-sectional view of the blind rivet used with an embodiment of a riveting tool according to the present invention in which the rivet body is inserted into a workpiece with a pre-fitted pulling mandrel in the unset state; Figure 2 is a schematic cross-sectional view of the blind rivet of Figure 1 after the setting operation; Figure 3 is a schematic cross-sectional view of the operating mechanism of an embodiment of a tool according to the present invention with the blind rivet in position to be set; Figure 4 is an enlarged view of the head of the tool shown in Figure 3; and Figures 5-11 are schematic perspective views showing the operating sequence of the riveting tool.

The structure and operation of the tool of this invention is the same as that of the tool described in U.S.

Patent No. 5,337,463 except as set forth in the above-described drawings and the following detailed description. Parts identified as numbers below 99 correspond to the similarly numbered parts in the aforementioned patent. The tool of this invention is used to set a blind rivet 100 of the type shown in the U.S.

Patent No. 5,403,135 and shown herein in Figures 1 and 2, to which the following description will now be referred.

Figure 1 shows the workpiece 1 which consists of a sheet metal plate and into which the blind rivet body 2 is inserted, more specifically in its original state prior to deformation by the setting process. The hole 3 in the workpiece 1 receives the rivet tube or body 2 of the blind rivet 100 so that the flange 4 then rests against the workpiece 1. On the side of the rivet body remote from the flange 4 is a portion 6 of the rivet body which is provided with an internal thread 7 for receiving the self-tapping screw-mandrel 9, as more fully described in US Patent No.

5,403,135. Adjacent to the portion 6 is the clinch zone 8 having a thinner wall than the base of the rivet body for purposes of deformation, as shown in Figure 2. The screw-mandrel 9 is seen to have a pulling head or cap 10 that serves as an abutment for the setting tool during the setting process as described below.

The collet assembly of the present invention differs from that described in the US Patent No. 5,337,463 in that each of the collet segments 101 are shaped as best shown in Figure 4 and specifically include a rearwardly facing chamfered surface 102. The O-ring shown in the prior patent has been removed and the washer 51 is now positioned behind the rear face of the segments 101, which are held together by means of the spring 52 (see Figure 3) which urges them against the conical surface 30.

A rod 103 extends through the bore 34 of the housing 12 and into a cap 104 on the rear end of the tool. A spring 105 biases the rod 103 forwardly against a back wall 106 of the housing 12 and toward the chamfer 102. A pulling piston 107 for operating the tool and setting the rivets is also shown in position in the housing 12.

In operation the collet segments 101 are held together by the latching operation of the head or cap 10 of the screw-mandrel 9 (which bears against the back latching surface 108 of the collet assembly) and the flange 4 of the rivet (which forces the abutment members 54 rearwardly into the closed position). Thus the rear chamfer 102 moves the rod 103 into the cap 104 against the pressure of the spring 105.

As soon as the tool trigger is released, pressure on the piston 107 is removed. Spring 68 moves the abutment assembly forward and spring 105 drives the rod 103 into the chamfer 102, thus forcing the collet segments 101 apart.

This action releases the head of the mandrel so that the tool can be removed. Since the mandrel is also a screw as described in US Patent No. 5,403,135, the mandrel can then be removed from and reinserted into the rivet body 2.

The sequence of the tool operation is shown in Figures 5-11. The steps of introducing a rivet 100 into the tool are shown in Figures 5 and 6. The rivet is shown latched in place in Figure 7. The setting operation is shown in Figures 8 and 9, and Figures 10 and 11 show the process of opening the collet segments 101 of the collet assembly so that the tool can be removed from the screw mandrel 9.

Claims

1 A riveting tool for setting a tubular rivet (100) having a body (2), a head (4) and a mandrel (9) in the body (2) having a pulling head (10) to move the mandrel (9) relative to the rivet body (2) to set the rivet (100), the mandrel (9) remaining in the body (2) after the tool is removed, the tool comprising a nosepiece a pulling assembly mounted in the nosepiece and arranged to grip the pulling head (10) of the mandrel (9) and being movable relative to the nosepiece to pull the mandrel (9) to set the rivet (100), the pulling assembly including collet members (101) for latching behind the mandrel head (10), an abutment assembly (54) mounted on the nosepiece and arranged to engage the head (4) of the rivet body (2) during the setting of the rivet (100) and comprising a plurality of abutment members (54) extending generally axially of the nosepiece around the pulling assembly and movable axially between an open position in which the pulling head (10) of the mandrel (9) may be passed through the abutment assembly (54) to be subsequently engaged by the pulling assembly and a closed position, in which the abutment members (54) provide an abutment engaging the rivet head (4), and a rod member (103) having a cam surface for opening the collet members (101) to release the mandrel head (10) after the rivet (100) has been set and the pulling assembly has been released.

2 A riveting tool according to claim 1, characterised in that the mandrel (9) is threaded and cooperates with a threaded portion (6) in the rivet body (2).