GB2409995A

GB2409995A - Banding Tool

Info

Publication number: GB2409995A
Application number: GB0507511A
Authority: GB
Inventors: Steven John Blanks; Paul Andrew Gingell; Andrew William Dunkerley
Original assignee: Spirent PLC
Current assignee: Spirent PLC
Priority date: 2002-02-19
Filing date: 2003-01-16
Publication date: 2005-07-20
Anticipated expiration: 2023-01-16
Also published as: GB0507512D0; GB2409994A; GB2409996A; GB2409994B; GB2409995B; GB0507511D0; GB2409996B; GB0507510D0; EP1338513A1

Abstract

A banding tool for tensioning, cutting and fastening the head of a metal banding fastener includes a folding bar 46 which is advanced towards the underside of the strap in the direction of the head 10 of the strap, a jaw 21 on the tool constraining the head against movement in the direction of movement of the folding bar. V-shaped projections on the jaw 21 of the tool are arranged to engage with complementary v-shaped notches 60 in the edge of the head of the fastener, to ensure that the fastener engages correctly with the tool and to prevent the fastener from displacing during tensioning.

Description

Banding Tool This invention relates to a tool for tightening and securing

metal banding fasteners.

Metal banding fasteners are known for securing articles together securely. One such fastener comprises a flat head or buckle 10, as shown in Figure 1 of the drawings, which is formed of a stamped sheet of metal. A bridge 11 is formed in the head to define a passageway 12 which is directed across the head 10. A pair of spaced upstanding tabs 13 are formed on the outer end of the head.

A length of metal banding in the form of a flat strap 14 is cut from a roll and fastened at one end to the head 10, as shown in Figure 2 of the drawings. The strap 14 is fastened to the head 10 by feeding it across the head 10 from its inner end to its outer end, through the passageway 12. The strap is then folded downwardly through 180 around the outer end of the head 10 and fed back under the head 10, where it is passed through the opening formed under the bridge 11 to the top surface of the head 10. In this manner, the strap 14 is securely fastened at one end to the head.

Referring to Figure 3 of the drawings, the fastener can be used to fasten objects together by forming the strap 14 into a loop around the articles to be fastened, and inserting its free second end through the passageway 12 in the head 10. The strap 14 is then tightened and secured by folding it back on itself through about 90 over the bridge 12, whereupon the strap tensioning force can be released and any excess length of strap 14 can be cut off. The strap 14 is then permanently secured by folding it completely back on itself before folding the tabs 13 inwardly to constrain the cut end, as shown.

It will be appreciated that the fastener provides an extremely strong fastening around objects. However, such fastenings are difficult and time consuming to secure, particularly if any degree of tension is required in the strap.

Tools are known for tensioning such fasteners. One such tool engages the inner end of the head 10 and pulls the strap through the passage 12 until the desired tension is reached, whereupon a screwdriver or the like is used to wedge the strap 14 to the head 10 whilst the strap is cut and folded. Whilst this tool enables the strap to be tensioned, it does nothing to simplify the fastening procedure.

In accordance with this invention, there is provided a banding tool comprising means for engaging a substantially flat head of a fastener, a slidable folding member arranged for movement towards said head engaging means in a direction which extends substantially parallel to the plane in which said head of the fastener is disposed, in use of the tool, said head engaging means being arranged to constrain said head of the fastener against movement in said direction.

A problem of tensioning fasteners using a tool is that the head of the fastener needs to be located correctly in the jaws of the tool, otherwise the tool could jam or an unsatisfactory fastening could be formed. Also, there is a risk that persons could jam or damage the tool by using a type of fastener which is not designed for use in a tool.

Preferably therefore, in a fastener in accordance with this invention, the head engaging means comprises at least one formation arranged to engage with a complementary formation provided on said flat head of the fastener.

The or each of the formations on the tool engages with the complementary formation on the head of the fastener, thereby ensuring that the head of the fastener engages correctly with the tool and preventing the fastener from displacing during tensioning. The formations also prevent incorrect fasteners from being used, particularly if at least one formation on the tool is a projection which extends into a complementary cut-out on the fastener, since it will not be possible to fit a fastener to the tool unless it has the appropriate cut-out for receiving the projection on the tool.

Preferably said head engaging means of the tool comprises a pair of jaws for clamping onto the head of the fastener.

Preferably two formations, in the form of respective projections, are formed on at least one of the jaws of the tool.

Preferably each of these projections is v-shaped.

An embodiment of this invention will now be described by way of example only and with reference to the accompanying drawings, in which: Figures 13 are perspective views showing how a conventional metal banding fastener is assembled and fastened; Figure 4 is perspective view, from the left side and above, of a banding tool in accordance with this invention, with some parts being omitted for clarity; Figure 6 is a perspective view, from the right side and below, of the banding tool of Figure 4, with some parts being omitted for clarity; Figure 7 is a similar view to Figure 6, with some further parts being omitted for clarity; Figure 8 is a perspective view from the left side and above, of the tool of Figure 4, with some parts being omitted for clarity; Figure 9 is a perspective view, from the left side and above, of the tool of Figure 4, with some further parts being omitted for clarity and with the blade in its raised position; Figure 10 is a similar view to Figure 9, with the blade in its cut position; Figure 11 is a similar view to Figure 9, with some further parts being omitted for clarity; Figure 12 is a rear end view of the tool of Figure 4; Figure 13 is a perspective view of the head of a fastener for use with a modified embodiment of banding tool in accordance with this invention; and Figure 14 is a perspective view of the head of an alternative fastener for use with an alternatively modified embodiment of tool in accordance with this invention.

Referring to Figures 4 to 11 of the drawings, there is shown a banding tool for operation by a rotary power tool such as a cordless drill or electric screwdriver (not shown).

The banding tool comprises a pair of jaws 20, 21 on its underside adjacent the front of the tool for clamping onto the head 10 of a conventional metal banding fastener of the kind shown in Figures 1 to 3. Before the tool is engaged with the head 10, the strap 14 is formed into a loop around the objects to be fastened and the free end of the strap 14 inserted under the bridge 11.

The projecting length of strap 14 is inserted into the tool through an opening formed between the jaws 20, 21, where it passes up an inclined rampway 23 towards a slotted bobbin 24 mounted for rotation about an axis which extends parallel to the axis of the strap 14. The strap 14 extends through one of several slots 25 extending diametrically through the bobbin 24.

Once the strap 14 has been loaded into the tool as described, the strap 14 is pushed further into the tool until the inner edge of the head 10 is received in a slot 26 formed in the inner jaw 20. The outer jaw 21 is then pivoted rearwardly about an axis which extends parallel to the rotational axis of the bobbin 24, by urging a lever 18 forwards, to cause the outer edge of the head 10 of the fastener to be received in a slot 27 formed in the outer jaw 21. In this position, the head 10 of the fastener is securely locked to the tool. In fact, the tool can be released, since it is able to support itself on the fastener.

The fastener is now ready for tightening and in order to achieve this, the user connects a hexagonal-section bit mounted in his drill to a hexagonal socket 28 formed on the end of a first rotary shaft 29 and accessible through a slot 30 formed in the casing 31 of the rear end wall of the tool.

The shaft 29, which extends longitudinally of the tool, is provided with a worm drive 32 engaged with the teeth of a sprocket 33 which is coupled to the bobbin 24. Thus, rotation of the first shaft causes the bobbin 24 to turn, thereby winding the projecting end of the strap 14 around the bobbin.

Once the strap 14 is sufficiently tight, the drill can be disconnected from the shaft 29.

In order to cut the excess length of strap 14 wound around the bobbin 24, the user next engages his drill with a socket 34 formed on the end of a second rotary shaft 35 and accessible through the slot 30 in the rear end wall of the tool. The second shaft 35 extends parallel to the first shaft 29 and is provided with an external screw thread.

The opposite end of the shaft 35 extends into an internally screwthreaded bore formed in a slidable block 36.

The block 36 is connected to a plate 37 lying alongside the strap 14 in a plane which extends perpendicular to the plane of the strap. The plate 37 is formed with an elongate slot 38 which is inclined downwardly and forwardly towards the front of the tool.

An elongate cutting blade 39 is mounted across the bottom of the rampway 23 and extends transverse the strap 14.

The blade 39 comprises a projection at one end which is received in the slot 38 in the plate 37. The other end of the blade 39 is mounted for rotation about a horizontal axis which extends parallel to the longitudinal axes of the shafts 29, 35 on the opposite side of the rampway 23 to the plate.

The plate 37 is also connected on its underside to one end of a linkage bar 42 which is pivoted, intermediate its opposite ends, to the body of the tool for rotation about a vertical axis which extends perpendicular to the axes of the shafts 29, 35. The opposite end of the linkage bar 42 is connected to one end of a wedging member 43 slidably mounted under the rampway 23 for movement in the direction of the longitudinal axes of the shafts 29, 35. The opposite end of the wedging member 43 comprises upper and lower surfaces which converge into a point.

In use, rotation of the second shaft 35 causes the block 36 to move rearwardly towards the user. As the block 36 moves, the projection on the blade 39 travels down the inclined slot 38 in the plate 37, thereby causing the blade 39 to pivot downwardly. Also, as the block 36 moves rearwardly, the linkage bar 42 urges the wedging member 43 forwardly through an opening in the rear jaw 20 until it becomes wedged between the projecting length of strap 14 and the head 10 of the fastener.

The rear vertical face of the blade 39 abuts a hardened steel plate 40 fixed to the bottom of the rampway 23. Thus, as the blade 29 moves downwardly it bears against the hardened plate 40 and cuts the strap 14 transverse its longitudinal axis. The profile of the lower edge of the blade and/or the angle of the slot 38 may be varied to adjust the rate of movement and inversely adjust the cutting force, for example so that a large cutting force is initially provided at the point where the blade 39 first cuts the strap 14.

When the strap 14 is fully cut, the wedging member 43 is fully wedged between the strap 14 and the head 10, thereby maintaining the tension of the looped strap.

Next, the cut end of the strap 14 has to be folded over the bridge 11 of the head 10. This is achieved by the user engaging his drill bit with a socket 44 formed on the end of a third rotary shaft 45 and accessible through the slot 30 in the rear end wall of the tool. The third shaft 45 extends parallel to the other two shafts 29, 35 and is provided with an external screw thread.

The opposite end of the shaft 45 extends into an internally screwthreaded bore formed in an elongate folding bar 46 slidably mounted between the wedging member 43 and the underside of the rampway 23 for movement in the direction of the longitudinal axes of the shafts 29, 35.

As the shaft 45 rotates, the folding bar 46 moves forwards through an opening formed in the rear jaw 20 until it abuts the underside of the inclined length of cut strap 14 projecting from under the bridge 11 of the head 10. Continued movement of the bar 46 folds the projecting length of strap 14 back on itself over the bridge 11. As the bar 46 advances, it rides over the folded cut length of strap 14 until it abuts the upstanding tabs 13 on the head 10. The underside of the bar 46 is formed with channels or slots 47 having respective outer side surfaces which converge away from the front edge of the bar 46. The tabs 13 are received in the respective channels 47 of the advancing bar 46 and are thus brought together as the channels 47 converge, thereby constraining the folded cut end of the strap on the head 10.

Once the fastener has been secured, as herein before described, it can be released from the tool by opening the jaws 20, 21. The shafts 29, 35 and 45 are then rotated in the opposite direction to return the tool into a state where it is ready for use again.

The tool is straightforward to use, since all that is required is a conventional rotary power tool such as a cordless drill or screwdriver. The three sockets 28, 34, 44 are arranged in sequence across the slot 30 and thus the user merely has to move from one socket to the next (e.g. right to left) to perform the correct fastening sequence. In this manner, the user requires a minimal amount of training to operate the tool.

In an alternative embodiment, the tool is provided with an integral rotary power source, with a mechanism being provided for driving each shaft in the correct sequence.

In a further embodiment, some or all of the shafts, such as the second and third shafts 35, 45, are linked, for example by an idler mechanism, such that the shafts turn in sequence by driving only one or two shafts. In this manner, the operation of the tool is further simplified.

Referring to Figure 13 of the drawings, there is shown the head of a metal banding fastener which is similar to the fastener of Figures 1 and 2 and like parts are given like reference numerals. A pair of v-shaped notches 60 are formed in the edge of the head 30 at the outer end thereof on opposite sides of the passageway 12.

In use, the v-shaped notches 60 in the head 30 engage with complementary v-shaped projections (not shown) on the jaws 20, 21 of the tool, thereby ensuring that the fastener engages correctly with the tool and preventing the fastener from displacing during tensioning. The formations also prevent incorrect fasteners from being used with the tool.

Referring to Figure 13 of the drawings, in an alternative embodiment, the v-shaped notches 60 can be formed in the edge of the head 30 at the inner end thereof on opposite sides of the passageway 12.

Claims

Claims 1. A banding tool comprising means for engaging a substantially

flat head of a fastener, a slidable folding member arranged for movement towards said head engaging means in a direction which extends substantially parallel to the plane in which said head of the fastener is disposed, in use of the tool, said head engaging means being arranged to constrain said head of the fastener against movement in said direction.
2. A banding tool as claimed in claim 1, in which said head engaging means comprises at least one formation arranged to engage with a complementary formation provided on said flat head.
3. A banding tool as claimed in claim 2, in which the or each said formation on the tool comprises a projection arranged to extend into a complementary cut-out on said head of the fastener.
4. A banding tool as claimed in claim 3, in which the or each said projection is v-shaped.
5. A banding tool as claimed in any of claims 2 to 4, in which said head engaging means comprises a pair of jaws for clamping onto said head of the fastener.
6. A banding tool as claimed in claim 5, in which two said formations are formed on at least one of the jaws of the tool.