GB2360554A - A hand tool for tightening a strap around a rubber gaitor for a motor vehicle joint - Google Patents

Abstract

A hand tool for tightening a strap around a rubber gaiter for a motor vehicle joint has a slotted end guide (22) for the strap and a spaced shaft (12) around which the strap is wound. The shaft (12) is rotated with a manual turning device (14) which winds the strap around the shaft until the abutment surfaces are abutted against the strap locking fastener (54 in Figs 13 and 14). At this point, further rotation of the shaft (12) draws the strap through the fastener , thereby tightening the fastener in place about the gaiter. The surplus end section of the strap wound around the shaft (12) can then be severed with a rotatable cutter (60) on the tool operated by the lever (62).

Description

2360554 TIGHTENING APPARATUS The present invention relates to apparatus

and a method for use in tightening a strap or clip fastened around a body particularly, but not exclusively, for tightening straps of the kind used to clamp tubular rubber gaiters in place around the joints of motor vehicles.

It is common practice to secure tubular rubber gaiters in place around the joints e.g. constant velocity, steering joints of motor vehicles, using metal or plastics straps or clips which are fastened tightly around respective annular seating portions of the gaiter.

The gaiter must be fastened tightly in place to prevent slipping of the gaiter relative to the joint members of the joint and to prevent the ingress of dirt and moisture and the egress of lubricant.

Typically, the straps used to secure gaiters incorporate a self-locking fastener at one end. The strap is wrapped around the gaiter seating portion, and the opposite free end portion of the strap drawn through the fastener to tighten the strap in place. Thus tightening of the strap requires that the fastener is supported while the free end of the strap is tensioned, or vice versa.

The conventional method of tightening the strap involves butting the fastener against the gaiter with a pair of pliers or similar tool whilst the free end is pulled through the fastener to tension the strap, thus tightening it in place around the gaiter. This method is extremely awkward and time consuming.

Also, whilst the surfaces of certain straps, such as metal straps, are smooth and difficult to grip, the edges of such straps are normally very sharp. This makes manipulation of the straps difficult and the above method and apparatus necessitates the use of either protective gloves and/or a further, second tool to pull the free end in order to prevent injury.

It is an object of the present invention to overcome the above identified problems by providing a safer and more efficient apparatus and a method for tightening straps of the above described kind.

Accordingly, in a first aspect therefore, there is provided apparatus for use in tightening an elongate strap fastened around a body, the strap having one end portion incorporating locking means and an opposite free end portion which is drawn through or via the locking means to tighten the strap around the body, the device comprising a handle which has rotatable tensioning means to tension longitudinally the strap, guide means via or through which the strap is fed to the tensioning means and abutment means for abutment against the locking means, whereby the strap can be drawn through the locking means, by rotation of the tensioning means to tighten the strap around the body.

In a further aspect, there is therefore provided a method for 1 1 tightening an elongate strap fastened around a body, the strap having one end portion incorporating locking means and an opposite free end portion which is drawn through or via the locking means to tighten the strap around the body and using a device of the first aspect of the invention, the method comprising the steps of 1. feeding the free end portion of the strap to the tensioning means via the guide means; 2. abutting the abutment means against the locking means; 3. rotating the tensioning means to draw the strap through/via the locking means thereby tensioning the strap around the body.

The handle may take any suitable form but preferably is an elongate member.

The rotatable tensioning means may take any suitable form but preferably this includes a shaft of any suitable shape, e.g. cylindrical, which may project from the handle. Preferably the shaft is configured for winding of the strap thereupon.

Preferably, the shaft incorporates retaining means for retaining the free end of the strap. Conveniently the retaining means comprises a slot or aperture in the shaft for receipt of the said free end portion. This prevents slippage of the strap, relative to the shaft, during winding.

Advantageously, the retaining means is an open slot in the end portion of the shaft.

c With this arrangement, when sufficient tension has been applied to the strap, the strap wound on the shaft may be cut from the fastened strap and removed by sliding off the rotation device.

Whilst the use of a simple design is preferred, the invention is not intended to be restricted to the use of a rotatable shaft upon which the strap may be wound. Indeed, any suitable tensioning device may be used, and would include arrangements of multiple shafts or cogs, such as counter rotating shafts with gripping means such a friction surfaces, intermeshing teeth etc.

Preferably, the shaft is rotatable by means of a manual turning device which may take any suitable form.

The manual turning device may take any suitable form and may, for example, be an extension of the shaft, so that a single shaft provides both the tensioning means and its associated handle.

The main handle may support a single shaft rotatably mounted in an aperture in the main handle. The shaft and manual turning device may project from opposite sides of the main handle.

The manual turning device may incorporate one or more levers to facilitate the rotation of the manual turning device. In a preferred embodiment, the manual turning device comprises a first shaft which is rotatably mounted generally perpendicular to the main handle axis, and which supports one or more rods extending radially from the shaft.

1 -5 With this arrangement, the rods act as levers to facilitate rotation of the manual turning device.

The guide means may take any suitable form but preferably, comprises an open slot. The provision of an open guide slot means that the strap can be easily removed if required e.g. when the tightening operation has finished. Alternatively, an aperture or other guide member can be used.

In a particularly preferred embodiment, the main handle incorporates one or more flanges or folded portions which are configured to define an open guide slot. The flange(s) or fold(s) function to prevent the strap slipping out of the slot when in use.

Preferably, the guide slot and the tensioning shaft slot are dimensioned to be at least equal to, but preferably greater than, the width of the strap. This feature also helps to prevent the strap slipping out of the slots too easily.

It will be appreciated that the combination of an open guide slot and shaft projecting from the handle which has an open guide slot, provides for a tool which allows easy removal of the strap after tensioning, and requires no dismantling for such removal.

The abutment means may take any suitable form but preferably the surface forming the perimeter of the guide slot provides an abutment surface or surfaces for abutment against the locking member of the strap.

1 The apparatus may include a cutter for cutting the strap which is in place on the apparatus. The cutter may take any suitable form and may comprise one or more cutting edges and/or blades and/or surfaces.

Preferably, the cutter comprises a member rotatable to a cutting position in which it cuts the strap, but may alternatively or additionally be slidable into a cutting position.

In a preferred embodiment, the cutter comprises a generally semi cylindrical member which has at least one longitudinal edge forming or provided with a cutting edge or blade.

In a particularly preferred embodiment the above cutter rotates within a semi-cylindrical channel at least one of whose longitudinal cutting edges forms or is provided with a cutting edge/blade.

With this arrangement the first member of the cutter is rotatable relative to a second member, the aforesaid channel for example, whose respective cutting edges are interoperable giving rise to the cutting of the strap.

The cutting edges of the cutter may be inclined. This feature provides for a more efficient cutting mechanism.

Whereas the invention has been described reference to tightening straps of the kind used to secure tubular rubber gaiters in place around a joint of a motor vehicle, the invention is not intended to be limited to such use.

The invention will now be described further by way of example only and with reference to the accompanying drawings in which:

Fig. 1 is an enlarged plan view of tightening apparatus in accordance with one embodiment of the invention; Fig. 2 is an underside view of the apparatus of Fig.1; Fig. 3 is a part perspective side view of the apparatus of Fig. 1; Fig. 4 is a perspective view of the apparatus of Fig. 1; Fig. 5 is a diagrammatic view of the underside of the apparatus of Fig. 1; Fig. 6 is a diagrammatic end view of the apparatus of Fig. 1; Fig. 7 is a diagrammatic end view of the apparatus of Fig. 1; Fig. 8 is a diagrammatic side view of the apparatus of Fig. 1; Fig. 9 is a diagrammatic side view of the manual turning device of the apparatus of figure 1, shown with main handle removed; Fig. 10 is a diagrammatic side view of apparatus in accordance -8with a further embodiment of the invention; Fig. 11 is a diagrammatic plan view of the apparatus of Fig. 10, shown with the main handle removed; Figs. 1 2A-F are diagrammatic views of the cutter components of the apparatus of Fig. 10; Fig. 13 is a diagrammatic view of a strap for use with the invention; and Fig. 14 is a diagrammatic view of the strap of Fig. 13 fastened (before tensioning) around a gaiter.

Referring to Figures 1-9, the tightening apparatus 1 comprises a main elongate handle member 2 which is fabricated from sheet metal. The edges are folded to form a shallow channel (when viewed in cross section). This shape provides for a strong but comparatively lightweight construction and is easy to grip. At one end 4, the edges are folded to form a pointed end portion with inclined, triangular side flanges 6 and 8. The respective edges 7 and 9 of the side flanges 6 and 8 together define a guide slot 22 which is open on one side 24 and which is bounded by abutment surfaces 3,5 which are formed from the surfaces of the edges 7 and 9 bounding the guide slot 22.

The main handle member 2 has an aperture which supports a shaft 11. This shaft is stepped in diameter, having a wide diameter portion 15 and a narrow diameter portion 13, and is supported by the aperture at the -9 inner end of the narrow diameter portion 13 so that the portions 13 and 15 project from opposite sides of the handle member 2. Movement of the shaft 11 transversely of the handle 2 is prevented by a self-locking spring steel washer 18.

The washer 18 may be locked into a smaller circumferential groove provided in the shaft 11 at an appropriate position.

A rotatable tensioning device 10 comprises the shaft portion 13 which forms the strap winding shaft 12 and has a open diametric slot 16.

A manual turning device portion 14 comprises an elongate rod secured in a diametric bore in the wide diameter portion 15 to project therefrom.

The tightening apparatus may be used to tighten a metal strap 50 used to secure a tubular rubber gaiter 52 in position about a joint of a motor vehicle. As shown in figures 13 and 14, the metal strap 50 comprises a flat, thin, elongate strip of metal having one end portion incorporating a self-locking fastener 54 and an opposite free end portion 56 which is drawn through the self-locking fastener to tighten the strap 50 around the body.

In use, the free end 56 of a strap 50 fastened around a gaiter 52, is fed into the open guide slot 22 and then to the shaft slot 16. It is to be noted that these slots are located on a common side of the handle which facilitates fitting and removal of the strap to and from the apparatus. The slots 16 and 22 are also commonly aligned relative to the axis of the handle. Thus the strap follows a straight and direct path to the tensioning means 10.

It is also to be noted that the use of open slots 16 and 22, as opposed to apertures enables greater access to the slots and facilitates easy and quick fitting of the strap 50 in the apparatus 1.

Once the end portion 56 has been fed to the shaft slot 22, the strap winding shaft 12 is rotated by turning the manual turning device 14 which, by virtue of the relative flexibility of the thin strap bends the strap end portion at the edge of the slot 22 and as the shaft is turned further the strap is wound around the shaft. This continues until the abutment surfaces are abutted against the strap locking fastener 54. At this point, further rotation of the strap winding shaft draws the strap through the fastener (which does not slip back due to its self-locking construction), thereby tightening the fastener in place about the gaiter. It will be appreciated that by holding the main handle 2 in one hand and the manual turning device 14 in the other, the tightening operation can be performed in a very natural and efficient manner.

Further, the main handle and manual turning device carry respective plastic sleeves 90 and 91 to provide for a secure grip.

The excess strap now wound on the shaft 12 may be trimmed whilst retained in the apparatus 1 or trimmed after removal by tipping the apparatus 1 to one side to orientate the slots 22 and 16 downward so that the strap 50 slips out.

Referring now to figures 10 - 12, a second embodiment of the invention, incorporating an integral cutter, will now be described. The apparatus 1 of this embodiment is as described for the first embodiment, except that the tensioning device 10 and associated manual turning device 14 are located at a further distance from the guide slot 22, and located therebetween is a cutter drum 60 with associated lever arm 62. The cutter drum 60 comprises the narrow end portion of a stepped shaft 64 rotatably mounted at its lower end 66 via a neck portion 67 which fits in an aperture in the main handle 2, and oriented parallel to the strap winding shaft 12.

The neck portion 67 retains the shaft 64 in place in the handle 2. The top of the shaft 64 is attached to the lever arm 62. ( This is more clearly shown in figure 12A a side view, and figure 1213, a plan view of the shaft/handle arrangement).

Attached to the main handle 2 at the position of the shaft 64 is a box portion 68 (more clearly shown in figures 12E, and 12F, which are an upper plan, a 3-dimensional view respectively of the box 68). The box 68 is comprised of a first generally rectangular enclosed portion 70 with a semi cylindrical channel 73, which is axially parallel with the tensioning shaft and axially aligned with the cutter drum 60. The box has a second open portion 71 of the same shape (indicated by shading in figure 12F). The box 68 also has a circular aperture 72 through which the cutter drum 60 extends. The configuration of the box, specifically, the open and enclosed portions provides cutting edges X and Y which are formed from the two longitudinal edges of the channel 73. The wide diameter portion of the shaft 64 rests on top of this box portion, 68.

The cutter drum 60 incorporates a first member 74 which comprises an generally semi-cylindrical section of the shaft having inclined longitudinal cutting edges 80,82. The cutting edges 80,82 of the first member 74 correspond with the cutting edges X and Y provided in the channel. The use of inclined cutting edges 80,82 provides for a more efficient cutting mechanism.

In use, the strap end is fed from the guide slot 22 via the open portion 71 (which, in fact, forms a large open slot) and then to the tensioning device 10. During a tightening operation, the cutter handle 64 is left to rest against the main handle by means of a folded portion 64a. In this position, the cutting edges 80,82 are separated from corresponding cutting edges X,Y. After tightening of the strap, the lever arm is rotated in direction Z to rotate the cutter drum 60 thereby bringing the cutting edges 80,82 to meet respective cutting edges X,Y which cuts the strap.

The excess strap cut from the strap fastened in place around the gaiter can then be removed by tipping the handle to orient the slots downward so that the excess slides out easily.

It is of course to be understood that the invention is not intended to -13be restricted to the details of the above embodiments which are described by way of example only.

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Claims (17)

1 Apparatus for use in tightening an elongate strap fastened around a body, the strap having one end portion incorporating locking means and an opposite free end portion which is drawn through or via the locking means to tighten the strap around the body, the device comprising a handle which has rotatable tensioning means to tension longitudinally the strap, guide means via or through which the strap is fed to the tensioning means and abutment means for abutment against the locking means, whereby the strap can be drawn through the locking means, by rotation of the tensioning means to tighten the strap around the body.

2. Apparatus according to claim 1 characterised in that the rotable tensioning means includes a shaft.

3. Apparatus according to claim 2 characterised in that the shaft incorporates retaining means for retaining the free end of the strap.

4. Apparatus according to claim 3 characterised in that the retaining means comprise a slot or aperture in the shaft.

5. Apparatus according to claim 4 characterised in that the retaining -15means is an open slot in the end portion of the shaft.

6. Apparatus according to any one of claims 2 to 5 characterised by the provision of a manual turning device for rotating of the shaft.

7. Apparatus according to claim 6 characterised in that the turning device comprises an elongate member projecting transversely from an extension of the shaft.

8. Apparatus according to any one of claims 1 to 7 characterised in that the guide means comprises an open slo t.

9. Apparatus according to any one of claims 1 to 8 characterised by the provision of a cutter for cutting off a surplus free end portion of the strap. 15

10. Apparatus according to claim 9 characterised in that the cutter comprises a first member rotatable relative to a second member with interoperable cutting edges respectively on the member. 20

11. Apparatus according to claim 10 characterised in that the cutter is provided with a lever arm for rotating the first member.

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12. A method for tightening an elongate strap fastened around a body, the strap having one end portion incorporating locking means and an opposite free end portion which is drawn through or via the locking means to tighten the strap around the body and using a device of the first aspect of the invention, the method comprising the steps of 1. feeding the free end portion of the strap to the tensioning means via the guide means; 2. abutting the abutment means against the locking means; 3. rotating the tensioning means to draw the strap through/via the locking means thereby tensioning the strap around the body.

13. A method according to claim 12 characterised in that the strap wound on the shaft is cut from the fastened strap between the tensioning device and the abutment surface leaving a cut section of the strap wound around the said tensioning device which is then slidably removed.

14. A method according to claim 12 or 13 when using the apparatus of any one of claims 1 to 11.

15. A method according to any one of claims 12 to 14 when applied to, the tightening of a strap around a tubular rubber gaiter.

1 1 -17

16. Apparatus according to claim 1 substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

17. A method according to claim 12 substantially as hereinbefore, described.