WO2013057692A1

WO2013057692A1 - Scaffold clamp

Info

Publication number: WO2013057692A1
Application number: PCT/IB2012/055698
Authority: WO
Inventors: Lee Lipinski
Original assignee: Lee Lipinski
Priority date: 2011-10-19
Filing date: 2012-10-18
Publication date: 2013-04-25
Also published as: GB201118064D0; GB2495746A; GB2495746B; GB2510304B; GB201408733D0; GB2510304A

Abstract

A scaffold clamp Scaffold clamps are known wherein they are held closed by a nut and bolt arrangement. The bolt often extends outwardly from the clamp creating a hazard. The invention provides a scaffold clamp (10) wherein the bolt (118) extends inwardly towards the clamp (10). It also comprises a means (132) for preventing the bolt (118) from being completely withdrawn from the nut (120) so as to prevent loss thereof.

Description

Scaffold Clamp

The present invention relates generally to a scaffold clamp and finds particular, although not exclusive, utility in preventing hazards and loss of equipment.

Scaffolding clamps are often 'C' shape in nature having an openable jaw held closed by a nut and bolt. When walking in and around scaffolding, the bolt thread portion protrudes from the clamp that it is connected to, causing items of clothing to be snagged and parts of the body to be banged or injured.

This can mean that the simple task of working in and around scaffolding clamps becomes a matter of avoiding protruding bolts threaded portions in order to avoid catching clothing and skin.

To overcome this, the present invention proposes a bolt for a scaffolding clamp that does not have an exposed thread portion protruding from a fastened (locked or closed) clamp or an unfastened (unlocked or open) clamp.

The present invention is retrofittable to existing clamps with no, or only slight adjustment.

In one aspect, the invention comprises a scaffold clamp comprising a jaw for receiving a scaffold tube, the jaw being configured to move between an open position and a substantially closed position, the clamp also comprising a lock for releasably holding the jaw in the substantially closed position, the lock comprising a bolt and a long collar nut, the nut having an internal bore being partially threaded and an internal stop, the bolt having an external threaded tail being complementary to the internal thread of the nut, wherein the bolt-tail includes a portion which is bendable by application of a force after or upon insertion into the nut such that in use the bolt bends about its longitudinal axis so as to substantially prevent the bolt being completely withdrawn from the nut.

The force could be provided by a ram inserted into an open end of the nut, opposite from the end in which the bolt has been inserted. The ram pushes against the bolt-tail and bends it slightly to prevent it from being completely withdawn from the nut. However, the bolt can still be unscrewed enough to unlock the clamp.

Alternatively, or additionally, the bolt-tail may include a transverse slot substantially perpendicular to the length of the bolt-tail, and the nut may include an internal stop, the bolt-tail may be configured to bend about the slot as the end of the tail engages the internal stop.

In other words, when the bolt is fully tightened up after being fitted into the nut, the distal end of the bolt-tail will contact with the internal stop and 'crush-over'. This will 'off-line' the thread, thus preventing it coming out of the collar nut. If the thread part of the nut is located towards the end of the nut in which the bolt may be inserted and the portion of the bolt-tail which is unbent is longer than the threaded portion of the nut then the bolt may be unscrewed a certain distance before the bent portion reaches the threaded portion of the nut. Thus the lock may still be loosened so that it may be opened and the scaffold tube removed or inserted therein. However, the bent portion of the bolt-tail will prevent the bolt from being completely removed and thus possibly lost.

The transverse slot may extend through the width of the tail equal to greater than halfway. It may be less than halfway in one embodiment.

The transverse slot may be arranged approximately 1mm from the distal end of the bolt-tail. Other positions are possible such as within 1 to 10mm from the distal end of the bolt-tail.

The internal stop may be removable from the nut. For instance a bar could be temporarily positioned from the open end or from another aperture in the body of the nut against which the end of the bolt-tail may press as it is screwed into the nut. Alternatively, it may be integral with the nut.

The scaffold clamp may be configured so that the tail of the bolt does not project outwardly of the clamp when the jaw is in the substantially closed position. Rather, it projects inwards.

The clamp may be connected to another structure such as another clamp so that two scaffold tubes may be removably attached together.

The jaw may include two arms and a bolt-tail slot may be provided at the end of one arm through which the bolt-tail passes, in use, the bolt having a hexagonal head and flange being larger than the bolt-tail slot to prevent their passage therethrough.

The nut may be pivotably attached to the clamp. The nut may include a pivot hole or slot through which it is attachable to the clamp. The clamp may include a pivot configured to pass through the pivot hole or slot, the pivot being the internal stop. Alternatively or additionally, the bolt is pivotably attached to the clamp. The bolt may therefore include opposing arms at one end through which it is attachable to the clamp.

The nut may be adapted to receive the threaded bolt that is pivotally mounted on an outer portion of the 'C' shaped clamp.

The nut may be hollow. It may be hollow all the way through or only substantially or partially hollow all the way through.

In one embodiment, the nut has a first end and an opposite second end, the first end being arranged to receive the bolt-tail, the internal thread extending for a distance of between 5 and 15mm from the end first end towards the second end.

The internal stop may be arranged towards the second end.

The nut may include a shaped head for permitting rotation of the nut with a tool, the head being located at towards or at the second end. The nut may include a hexagonal nut located at the second end. It may be rectangular in shape.

In either case, the risk of snagging of clothing and/or injury to the person is reduced as the hexagonal head of the nut and/or bolt presents a more user friendly environment.

The above and other characteristics, features and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention. This description is given for the sake of example only, without limiting the scope of the invention. The reference figures quoted below refer to the attached drawings.

Figure 1 is a perspective view of a prior art scaffold clamp;

Figure 2 is a perspective view of one embodiment of the present invention;

Figure 3 is a perspective view of a nut according to an embodiment of the present invention;

Figure 4 is a cross-sectional side view of the nut of Figure 3;

Figure 5 is an elevational view of a bolt according to an embodiment of the present invention;

Figure 6 is a perspective view of the bolt of Figure 5 partially inserted into the nut of Figure 3;

Figure 7 is a perspective view of the bolt of Figure 5 more fully inserted into the nut of Figure 3;

Figure 8 is an elevational view of the nut of Figure 5 with its end bent;

Figure 9 is an elevational side view of an alternative nut from a first position;

Figure 10 is an elevational side view of the nut of Figure 9 from a second position being 90 degrees from the first position;

Figure 11 is a perspective view of the nut of Figures 9 and 10;

Figure 12 is a perspective view of another alternative nut;

Figure 13 is a cross-sectional side view of the nut of Figure 12;

Figure 14 is an elevational side view of an alternative bolt from a first position; and

Figure 15 is an elevational side of the bolt of Figure 14 from a second position being 90 degrees from the first position.

The present invention will be described with respect to particular embodiments and with reference to certain drawings but the invention is not limited thereto but only by the claims. The drawings described are only schematic and are non-limiting. In the drawings, the size of some of the elements may be exaggerated and not drawn to scale for illustrative purposes. The dimensions and the relative dimensions do not correspond to actual reductions to practice of the invention.

Furthermore, the terms first, second, third and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequence, either temporally, spatially, in ranking or in any other manner. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other sequences than described or illustrated herein.

Moreover, the terms top, bottom, over, under and the like in the description and the claims are used for descriptive purposes and not necessarily for describing relative positions. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other orientations than described or illustrated herein.

It is to be noticed that the term 'comprising', used in the claims, should not be interpreted as being restricted to the means listed thereafter; it does not exclude other elements or steps. It is thus to be interpreted as specifying the presence of the stated features, integers, steps or components as referred to, but does not preclude the presence or addition of one or more other features, integers, steps or components, or groups thereof. Thus, the scope of the expression 'a device comprising means A and B' should not be limited to devices consisting only of components A and B. It means that with respect to the present invention, the only relevant components of the device are A and B.

Reference throughout this specification to 'one embodiment' or 'an embodiment' means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases 'in one embodiment' or 'in an embodiment' in various places throughout this specification are not necessarily all referring to the same embodiment, but may refer to different embodiments. Furthermore, the particular features, structures or characteristics of any embodiment or aspect of the invention may be combined in any suitable manner, as would be apparent to one of ordinary skill in the art from this disclosure, in one or more embodiments.

Similarly, it should be appreciated that in the description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in fewer than all features of a single foregoing disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this invention.

Furthermore, while some embodiments described herein include some features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention, and form yet further embodiments, as will be understood by those skilled in the art. For example, in the following claims, any of the claimed embodiments can be used in any combination.

In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the invention may be practised without these specific details. In other instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

In the discussion of the invention, unless stated to the contrary, the disclosure of alternative values for the upper or lower limit of the permitted range of a parameter, coupled with an indication that one of said values is more highly preferred than the other, is to be construed as an implied statement that each intermediate value of said parameter, lying between the more preferred and the less preferred of said alternatives, is itself preferred to said less preferred value and also to each value lying between said less preferred value and said intermediate value.

The use of the term 'at least one' may, in some embodiments, mean only one.

The invention will now be described by a detailed description of several embodiments of the invention. It is clear that other embodiments of the invention can be configured according to the knowledge of persons skilled in the art without departing from the underlying concept or technical teaching of the invention, the invention being limited only by the terms of the appended claims.

Figure 1 shows a prior art scaffold clamp 10 wherein the clamp comprises a jaw having two

arms

12, 14 pivoted together at a pivot point or hinge 16. A bolt 18 is pivoted to one of the arms 12 of the jaw at an end distal from the pivot point 16. In use it extends through a slot provided in the other arm 14. The jaw is closed by turning a nut 20 on the bolt 18 so as to pull the two

arms

12, 14 of the jaw closer together. This leaves a length of bolt 18 projecting outwardly from the clamp 10 which may cause injury.

In Figure 2 a general arrangement of one embodiment of the invention is shown. The clamp 110 has two

arms

112, 114 pivoted together at a pivot point 116 located at one distal end of the arms forming a jaw. The jaw describes an approximate circular shape such that scaffold tubing may fit therethrough and be clamped therein. These features are fairly typical of scaffold clamps.

The jaws are openable and closable. They may be held together in a clamped state about a scaffold tube by a nut and bolt arrangement provided at the other distal ends of the arms.

In the embodiment shown, the nut 120 comprises a long collar nut pivotably connected at one end to the distal end of one of the arms 112. The distal end of the other arm 114 has a slot 116 formed in it. In use, a bolt 118 is wound into the end of the nut 120 and the shank or bolt-tail of the bolt 118 is passed into the slot 118. As the nut 118 is tightened-up by being screwed into the nut 120 a washer and/or the head of the nut, which is larger than the slot 116, will not pass through the slot 16 and thus will bear on the arm 114 and draw it closer to the other arm 112, thus closing the jaw.

A view of another nut 220 is shown in Figure 3. It has a substantially cylindrical body 260 with a conical portion at one end 222 reducing the diameter. The body 260 includes a pair of diametrically opposed substantially circular holes 224 towards the other end (opposite from the conical end 222). These allow the nut to be pivotably attached to one arm of the clamp as will be understood by the skilled person.

The holes 224 may have different shapes than those shown such that a different method of attaching the nut to the clamp is required. For instance, pivotal wings could be used. The body 260 of the nut may also be a different shape to that shown.

Figure 4 shows that only the conical end 222 includes a threaded portion. The other features are as described above with reference to Figure 3.

A bolt 118 is shown in Figure 5. The bolt has a head 131 and a threaded bolt-tail portion 130 depending therefrom. A slot 132 is formed at the distal end of the bolt-tail. This may be a cut made in the tail, or the tail may be formed (such as by moulding) in this way initially.

In Figure 6 the bolt 118 is shown partially screwed into the nut 220. A washer 133 has been included beneath the head of the bolt 118 although the washer could be integral with the head of the bolt.

Figure 7 shows the bolt 118 more fully screwed into the nut 220 and Figure 8 shows the effect this has on the slot 132 at the end of the bolt 118. This bending of the thread on the side distally from the head of the bolt has been effected by the end of the bolt pressing against an internal stop (not shown) within the bore of the nut 220. This internal stop could be the pivot means passing through the holes 224 pivotably attaching the nut 220 to the clamp 110. Alternatively, or additionally an internal stop could be included in the bore of the nut. For instance a small tab projecting into the centre of the bore from the side wall may achieve the same effect. Alternatively, one end of the nut may be blocked off completely such that it is has a 'blind' end.

Although the slot 132 is shown at almost the very end of the bolt-tail it will be understood that it could be located further along the longitudinal length of the shank or bolt-tail of the bolt. The exact position may depend on the type of material used to form the bolt. For instance, with softer materials such as nylon or softer grades of metal the slot 132 could be located much further up the length of the bolt-tail.

Figure 9 shows an alternative embodiment of a nut 320. This also has a substantially cylindrical body 360 and a conical end portion 322. It also has diametrically opposed holes 324 provided at least partially through the body at the end opposite to the conical portion. However, as may be seen in figure 10 a slot 326 is also provided in the body 360. This slot extends from the end opposite the conical portion towards the conical portion end. It extends approximately two-thirds along the length of the body 360. A different view of this embodiment is shown in Figure 11. The slot 326 allows a tab (not shown) provided at the distal end of one arm 112 to pass therethrough. The nut 320 is pivotably attached to the tab by a bolt or other similar member as will be readily understood.

A different nut 420 is shown in Figure 12. It has a body 460 and includes a hexagonal head for rotating the nut with a spanner. The nut includes a portion 477 having a reduced diameter between the head 450 and the body 460. With reference to Figure 13, inside the body 460 a portion is threaded for receiving a correspondingly threaded bolt.

Figures 14 and 15 show an alternative bolt 218 from different view points. The bolt 218 includes a T bar portion 270 at one end. This T bar portion comprises two diametrically opposite extending arms. These arms extend away from the bolt 218 in a direction perpendicular to the longitudinal length of the bolt-tail 244. These arms allow for the bolt to be pivotably attached to the distal end of one of the

arms

112, 114 of the clamp 110. In use, the bolt may be used with the nut 420 depicted in Figures 12 and 13. The reduced diameter portion 477 may be placed in the slot 116 on one arm and screwed onto the bolt 218 which is pivotably attached to the other arm (not shown).

The bolt 218 includes a slot 232 which works in the similar way to that described above with reference to Figures 5 and 8. In this case, the nut 420 includes a blind end which abuts the distal end of the bolt-tail, when it is screwed into the bore of the nut, thus distorting the end of the bolt-tail and damaging the screw threads on the bolt-tail. The bolt-tail may bend about this slot such that the longitudinal axes of the two longitudinal length of the bolt-tail either side of the slot have different orientations, not being parallel. In one embodiment, the bolt-tail is irreversibly bent.

In one embodiment, the bolt may still be removed but a far higher torque is required than would otherwise be used. This removal may bend the bolt-tail back to its original alignment. Alternatively, a portion of the bolt-tail distal of the slot may snap off thus allowing the bolt to be removed relatively easily. It is also possible that the thread on the nut may be damaged by the removal of the bolt-tail.

Claims

A scaffold clamp comprising a jaw for receiving a scaffold tube, the jaw being configured to move between an open position and a substantially closed position, the clamp also comprising a lock for releasably holding the jaw in the substantially closed position, the lock comprising a bolt and a long collar nut, the nut having an internal bore being partially threaded, the bolt having an external threaded tail being complementary to the internal thread of the nut, wherein the bolt-tail includes a portion which is bendable by application of a force after or upon insertion into the nut such that in use the bolt bends about its longitudinal axis so as to substantially prevent the bolt being completely withdrawn from the nut.
The scaffold clamp of claim 1, wherein the bolt-tail includes a transverse slot substantially perpendicular to the length of the bolt-tail, and the nut includes an internal stop, the bolt-tail configured to bend about the slot as the end of the tail engages the internal stop.
The scaffold clamp of claim 2, wherein the transverse slot extends through the width of the tail equal to greater than halfway.
The scaffold clamp of either one of claims 2 and 3, wherein the transverse slot is arranged approximately 1mm from the distal end of the bolt-tail.
The scaffold clamp of any one of claims 2 to 4, wherein the transverse slot is arranged within 1 to 10mm from the distal end of the bolt-tail.
The scaffold clamp of any one of claims 2 to 5, wherein the internal stop is removable from the nut.
The scaffold clamp of any preceding claim, being configured so that the tail of the bolt does not project outwardly of the clamp when the jaw is in the substantially closed position.
The scaffold clamp of any preceding claim, wherein the jaw includes two arms and a bolt-tail slot is provided at the end of one arm through which the bolt-tail passes, in use, the bolt having a hexagonal head and flange being larger than the bolt-tail slot to prevent their passage therethrough.
The scaffold clamp of any preceding claim, wherein the nut is pivotably attached to the clamp.
The scaffold clamp of claim 9, wherein the nut includes a pivot hole or slot through which it is attachable to the clamp.
The scaffold clamp of claim 10 wherein the clamp includes a pivot configured to pass through the pivot hole, the pivot being the internal stop.
The scaffold clamp of any preceding claim, wherein the bolt is pivotably attached to the clamp.
The scaffold clamp of claim 12, wherein the bolt includes opposing arms at one end through which it is pivotably attachable to the clamp.
The scaffold clamp of any preceding claim, wherein the nut is hollow.
The scaffold clamp of any preceding claim, wherein the nut has a first end and an opposite second end, the first end being arranged to receive the bolt-tail, the internal thread extending for a distance of between 5 and 15mm from the end first end towards the second end.
The scaffold clamp of claim 15, wherein the nut includes a shaped head for permitting rotation of the nut with a tool, the head being located at towards or at the second end.
The scaffold clamp of claim 16, wherein the nut includes a hexagonal nut located at the second end.