GB2383966A

GB2383966A - Flexing spanner

Info

Publication number: GB2383966A
Application number: GB0200649A
Authority: GB
Inventors: Barry Paul Hartley
Original assignee: Individual
Current assignee: Individual
Priority date: 2002-01-12
Filing date: 2002-01-12
Publication date: 2003-07-16
Anticipated expiration: 2022-01-12
Also published as: GB2383966B; GB0200649D0

Abstract

The invention is a general purpose spanner that can automatically adjust to fit various nut size ranges. The spanner consists of two nut gripping jaws 11 and 12-15, each mounted onto one of two parallel bars 1 and 2 which are in turn linked by a circular hoop 3 region. (Figure 3). The parallel bars act like a pair of tongs, and by flexing the nut gripping aperture between the two jaws accommodates ranges of nuts. The two nut gripping jaws have opposite nut gripping angles that match two opposite corners of nuts to be accommodated. A rocker section 13 of jaw 12-15, ensures a parallel nut gripping aperture. The other jaw (opposite nut grip jaw) 11 is able to extend and retract to accommodate varying nut widths via a sliding mechanism 4-10 on the corresponding parallel bar. This is kept proportional to the widening or narrowing of the nut gripping aperture by a slide regulator 10 positioned between the two parallel bars. A guiding and restraining brace 6 prevents the parallel bars from being over stretched and over squeezed, thus also acting to limit the jaws movement. Handle grips 16 may be mounted on the parallel bars.

Description

FLEXING SPANNER The present invention relates to a general purpose spanner, and in particular to a spanner that is able automatically to adjust to fit a range of nut sizes.

There are many different types of spanner on the market that are for general use, both applied in industry and on a domestic level, e. g. in car maintenance. Such spanners generally take the form of a set of a number of solid non-adjustable spanners or ratchets. However, it can be tedious to search through a large set of spanners (often by trial and error) to find a spanner with the right aperture to accurately fit the nut to be manipulated. This is particularly the case when dealing with numerous nuts of varying size within a task. Alternatively, an adjustable wrench can be employed.

Unfortunately, this means that the aperture that is to accommodate a nut has to be manually adjusted to fit each size of nut. There is also the added problem that when a wrench is adjusted to fit a small sized nut, the head region/jaws are often too large, impeding access too, and manipulation of a nut, particularly if dealing with small tight spaces.

The invention aims to provide a spanner that can automatically adjust to fit variously sized nuts. This has the advantage that a user no longer need look for a spanner with a specific fit from a large set or have to manually adjust the nut fitting aperture. The invention may also be able to accommodate nuts in applications where there is restricted access better than a large wrench design.

The invention consists of two nut gripping jaws which are each mounted onto the ends of one of two parallel bars which are in turn linked together at one end by a circular hoop region. The parallel bars act like a pair of tongs, and by flexing together (by squeezing) the nut gripping aperture between the two jaws narrows to accommodate smaller size ranges of nuts. Conversely, by flexing apart (by stretching) the nut gripping aperture between the two jaws widens to accommodate larger size ranges of nuts. The two nut gripping jaws have opposite nut gripping angles that match two opposite comers of nuts to be accommodated. The fact that when flexing the pair of parallel bars beyond their parallel positions (at rest) means that the jaws would no

longer face each other parallel to accurately accommodate nuts. This is overcome by the counteracting movements of a rocker section of one of the jaws, so restoring a parallel nut gripping aperture. The other jaw (opposite nut grip jaw) is able to extend and retract to accommodate varying nut widths via a sliding mechanism on the corresponding parallel bar. This is kept proportional to the widening or narrowing of the nut gripping aperture by a slide regulator positioned between the two parallel bars.

A guiding and restraining brace prevents the parallel bars from being over stretched and over squeezed, thus also acting to limit the jaws movement.

The spanner would preferably be made from steel, e. g. stainless steel. But the possible presence of handle grips would preferable be made from a tough heavy duty moulded plastic. The spanner may be developed down two avenues. Either as a small set of e. g. three spanners, each with a different size range of nuts they accommodate. But they would be able to partially overlap some of each other nut accommodation size ranges.

This may be because in some application it could be desirable to maintain a locked grip on a nut on the release of the operator's grasp, rather than a spanner (the next size up) that would release its grip on a nut with the release of the operators grasp.

Alternatively, the spanner may be produced as a single spanner to accommodate a broad size range of nuts.

The invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figures la, lb and Ic show by way of side views the basic principal/concept of the spanners operation (not its full design), highlighting the initial problem associated with two parallel flexing bars when a spanner in accordance with the present invention is (a) at rest, (b) the bars are flexing together and (c) the bars are flexing apart; Figures 2a, 2b and 2c show by way of side views the operation of the spanner of Figures la-lc and mechanics that overcome the problem associated with two parallel flexing bars (a) at rest, (b) the bars are flexing together and (c) the bars are flexing apart; Figure 3 shows a perspective view of a spanner in accordance with the present invention;

Figure 4 shows and exploded view of the spanner of Figure 3; Figure 5 shows a perspective view of a second embodiment of the slide adjust regulator for the extending and retracting opposite nut grip angle jaw; Figure 6 shows a perspective view of a second embodiment of a spanner in accordance with the present invention; and Figure 7 shows a perspective view of a third embodiment of a spanner in accordance with the present invention showing a further example of a sliding mechanism for the extending opposite nut grip angle jaw with additional handle grips.

From Figure 1 of the spanners basic operating principal, its seen that when flexing the pair of parallel bars 1 and 2 beyond their parallel positions (at rest), that the two jaws 11 and 12-15 would no longer face each other parallel to accurately accommodate nuts, as in Figure la. Thus suffering from an under-bite Figure Ib and over-bite Figure Ic, respectively.

From Figure 2a, b and c of the spanners full design, its seen that there are features that address the under-bite and over-bite of the two nut gripping jaws 11 and 12-15 caused when flexing the pair of parallel bars 1 and 2 beyond their parallel positions (at rest).

This is achieved by the counteracting movements of a rocker section 13 of the jaw 12- 15, so restoring a parallel nut gripping aperture. The other jaw (opposite nut grip jaw) 11 is able to extend and retract to accommodate varying nut widths via a sliding mechanism 4-10 on the corresponding parallel bar 2. This is kept proportional to the widening or narrowing of the nut gripping aperture by a slide regulator 10 positioned between the two parallel bars.

From Figure 3 the same design example of spanner is shown in perspective, with Figure 4 showing the corresponding exploded diagram displaying all the spanners components, particularly with reference to those of the rocker jaw 12-15 and extending and retracting slide mechanism for the opposite nut grip jaw 11.

When the parallel bars 1 and 2 are flexed together, causing the two jaws to make contact with two opposite sides of a small nut, the rocker section 13 of the jaw (rocker jaw) 12-15 alters its position (facilitated by the springs 14) to maintain a parallel nut

gripping action (caused by the operators squeezing). This corresponds to the position to the opposite nut grip jaw 11. See Figure 2b.

When the parallel bars 1 and 2 are flexed apart, allowing the two jaws to make contact with two opposite sides of a large nut, the rocker section 13 of the rocker jawl2-15 shifts in the opposite direction. This again maintains a parallel nut gripping aperture corresponding to the relative position of the opposite nut grip jaw 11. See Figure 2c.

The opposite nut grip jaw 11 extends and retracts to accommodate varying nut widths relative to their height. This over comes the problem of under-bite and over-bites illustrated in Figure 1. A sliding mechanism 4-10 on the corresponding parallel bar 2, and a slide regulator 10 positioned between the two parallel bars, keeps this proportional to the widening or narrowing of the nut gripping aperture.

The sliding mechanism for the extending and retracting opposite nut grip jaw is assembled by the jaw being mounted onto a short bar 5, which is bonded to an outer hollow sheathing tube 4. This tube is free to slide up and down bar 2. The slide regulator 10 is attached between the two parallel bars 1 and 2 by pin 9 on bar 1, and the hollow sheathing tube 4 via component 7 and pin 8. See Figure 3 and Figure 4.

The stem of component 7 passes though a hole in the hollow sheathing tube 4 and fits into a groove on 2. This feature stops the opposite nut grip jaw from moving laterally from side to side. In addition component 7 only permits the jaw to retract to a certain point. The slide regulator 10 also prevents the hollow sheathing tube 4 and opposite nut grip jaw from sliding off bar 2.

From Figure 5 a second example of a slide regulator in the form of a bar 10 is displayed. This is mounted between the parallel bars by mounting to bar 1 in an identical way to bar 2 (via the hollow sheathing tube 4) using the same pivoting arrangement 9a, b as 7/8.

Whether the regulator 10 should take the form of a piece of flat stiff metal with a curve (Figure 3) or in the form of a straight bar (Figure 5) would depend on which would produce extension and retraction of the jaw 11 in a linear and proportional

relation to the widening and narrowing of the aperture to accommodate a nut. The sliding regulator 10 could also take the from of a curved bar or a straight flat stiff piece of metal.

The guiding and restraining brace 6 in FigureS 3,4 and 5 is attached to bar 1. But it allows bar 2 (and the sliding hollow sheathing tube 4) to flex together and apart in relation to bar 1. However the brace imposes a flexing limit to avoid over stretching of the parallel bars which may result in a permanent stretch.

From Figure 6 a second example of the spanner is shown in perspective, in which the length of the parallel bars have been shortened between the hoop 3 and the two jaws 11 and 12-15. This is so that with the addition of the handle grips 16, there is no change in the over all length of the spanner. These handles mounted to the parallel bars and extending past the circular hoop are to simplify the spanners operation when the nut griping aperture needs to be stretched to accommodate larger sizes of nuts.

From Figure 7 a third example of a spanner is shown in perspective, in which the hollow sheathing tube is replaced by a much thicker parallel bar 2 which is cast with a hollowed out channel (open from the top) for much of its length. It acts as a supporting rail (preventing any lateral side to side rotation) of the bar 5 which allows extension and retraction of the jaw 11. Bar 5, component 7 (which associates with the slide regulator 10) and the jaw 11 are produced from a single casting. The long wide slot in parallel bar 2 allows bar 5 to be connected to the slide regulator via section 7.

Parallel bar 1, component 9a (which associates with the slide regulator 10) and the main jaw section 12 (associated with the rocker jaw section 13, are also produced from a single cast. Such casting of multiple components together reduces the number of individual components. The flexing of the two parallel bars 1 and 2 and integrated jaws is achieved by the attached circular hoop 3 at their ends.

With the example given in Figure 3, the operator would have to insert their fingers between the two parallel bars behind the jaw aperture and stretch them apart to accommodate larger nut sizes. This would have to be repeated every time the operator

wishes to remove the spanner from the nut, before then repositioning it for another turn. But with the example given in Figure 6 and Figure 7 the operator would only have to squeeze the handle regions behind the circular hoop 3. When the nut griping aperture needs to be narrowed to accommodate smaller sizes of nuts, the parallel bars /handle region ahead of the hoop is squeezed.

It is imperative to recognise that although the presence of the handles 16 alters the operation of the spanner when employed to manipulate larger nuts than when the aperture size is at rest, the actual mechanics and features of the spanner invention are the same for each example of embodiment.

It may be possible to develop the spanner to more closely resemble a more conventional spanner by rounding off some of the edges, such as the outward facing regions of the two nut griping jaws as displayed in Figure 7.

Claims

CLAIMS 1 A spanner able to automatically adjust to accommodate various nut size ranges by the means of nut griping jaws connected to flexing bars joined by an apex region, and an adjusting region on a jaw, and a sliding device, with a regulating device mounted between flexing bars to allow the opposite jaw to extend and retract to accommodate varying nut sizes, and guiding and restraining feature to limit the flexing bars movement.
2 A spanner as claimed in Claim 1, consisting of two parallel bars linked at one end by a circular hoop which acts as an apex pivotal point which is of a less complex design than a hinged spring loaded device.
3 A spanner as claimed in Claim 1, has two nut gripping jaws, one mounted on each of the two parallel bars.
4 A spanner as claimed in Claim 1, wherein the bars are able to be flexed inwards by the operator squeezing, or flexed outwards by the operator stretching.
5 A spanner as claimed in Claim 4, wherein flexing the parallel bars together causes the two nut griping jaws to be moved closer together, and flexing the parallel bars apart causes the two nut gripping jaws to be moved further apart.
6 A spanner as claimed in Claim 4 and Claim 5, whereby the parallel bars and two nut gripping jaws move closer together causes the nut accommodation aperture to narrow to accommodate smaller nut sizes.
7 A spanner as claimed in Claim 4, Claim 5 and Claim 6, whereby the parallel bars and two nut griping jaws move further apart causes the nut accommodation aperture to widen to accommodate larger nut sizes.

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8 A spanner as claimed in Claim 5, whereby the two jaws are shaped to fit the comer angles on two opposite sides of a nut to be accommodated.
9 A spanner as claimed in Claim 1, has a jaw with an adjusting region.
10 A spanner as claimed in Claim 1 and Claim 9, whereby the adjusting region mounted on the jaw is a rocker section to adjust and compensate for the non-parallel moving together or moving apart of the two nut griping jaws caused by the flexing of the two parallel bars beyond their parallel resting position.
11 A spanner as claimed in Claim 10, whereby the rocker section allows the jaw to make a flush parallel contact with a nut, is mounted on the rocker jaw by a pivot and held in a neutral position at rest by two springs.
12 A spanner as claimed in Claim 1, has an opposite nut grip angle jaw that is able to extend and retract to accurately accommodate the width of different nut size ranges by means of a sliding device.
13 A spanner as claimed in Claim 12, whereby the sliding device is a hollow sheathing tube which slides up and down one of the two parallel bars and is attached to the opposite nut grip jaw by a short solid bar, thus giving it an extending and retracting ability.
14 A spanner as claimed in Claim 12 and Claim 13, whereby the extending and retracting opposite nut grip jaw is regulated from sliding/retracting too far back along the parallel bar or sliding/extending too far forward and off the end of the parallel bar by a regulator device.
15 A spanner as claimed in Claim 14, wherein the regulator is in the form of either a flat, stiff strip of metal (straight or curved) or a metal bar (straight or curved) linked between the two parallel bars via suitable linkage to the sliding hollow sheathing tube at one end, and the parallel bar at the other end.

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16 A spanner as claimed in Claim 15, whereby the regulator attachment on the sliding hollow sheathing tube has a stem which fits through the tube and into a groove on the corresponding parallel bar to prevent lateral side ways rotation of the extending and retracting opposite nut grip jaw.
17 A spanner as claimed in Claim 1 and Claim 12, whereby the alternative sliding device is a thick cast parallel bar which is hollowed out for much of its length, which acts as a support rail for the bar (which may be cast as part of the associated jaw) to slide back and forth within, thus giving the opposite nut jaw its extending and retracting ability.
18 A spanner as claimed in Claim 1, has a guiding and restraining brace and is attached to one parallel bar but allows the second parallel bar (and the sliding hollow sheathing tube) to flex together and apart in relation to the first parallel bar, but also imposes a flexing limit to avoid over stretching of the parallel bars which may result in a permanent stretch.
19 A spanner as claimed in Claim 1, can be developed down two avenues, either as a small set of spanners with partially overlapping size ranges for desired grip/hold applications, or as a single spanner able to accommodate a greater size range of nuts.
20 A spanner as claimed in Claim 1, could have additional handles mounted on the parallel bars which continue past the hoop region which may simplify the spanners operation when employed to accommodate larger nuts, when the parallel bars have to stretch.
21 A spanner substantially as herein described and illustrated in the accompanying drawings.