GB2432879A

GB2432879A - Clamping device

Info

Publication number: GB2432879A
Application number: GB0524642A
Authority: GB
Inventors: Trevor Neil Martin
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-12-02
Filing date: 2005-12-02
Publication date: 2007-06-06
Anticipated expiration: 2025-12-02
Also published as: GB2432879B; GB0524642D0

Abstract

A clamping device (for example a clothes peg) comprising first and second elongate body members 2,3 and a sinuous member 4 located between, and connecting, the body members. The first and second elongate body members each having a first end 5 to one side of the sinuous member and each having a second end 6 to an opposed side of the sinuous member. Wherein, in use, the first ends of the first and second elongate members may be moved towards one another such that the second ends of the first and second elongate members are moved apart. Movement of the first and second elongate members is accommodated by flexure of at least a portion of the sinuous member, wherein the portion of the sinuous member that flexes during movement of the first and second elongate body members is shaped to comprise at least one point of inflection.

Description

CLAMPING DEVICE

This invention relates to clamping devices and, in particular, to clothes pegs for securing clothes to a conventional flexible clothes line.

Clothes pegs are well-known in the art. Numerous prior art specifications describe clamping devices or clothes pegs that are, say, double ended (can clamp at either end) or are made of one piece. It is also known in the art to provide one-piece, double-ended clothes pegs. These pegs are particularly useful as they can clamp at either end and are relatively cheap to manufacture, as they are made in one piece. However, typical one-piece clothes pegs involve complicated arrangements of spring-like member to provide pivoting of armatures (handles and/or jaws) around the member. Further disadvantages are the clamping force produced is often far less than produced by a conventional peg having a metal spring element and, in order to provide a greater clamping force, the spring-like member is typically made more rigid and, therefore, more prone to wear and breakage during long-term use.

There is, therefore, a need for a one-piece, double-ended clothes peg without the associated disadvantages of prior art clothes pegs mentioned above.

The present invention seeks to provide such a clothes peg.

Accordingly, in an aspect the invention provides a clamping device comprising first and second elongate body members and a sinuous member, the sinuous member being located between, and connecting, the first and second elongate body members, the first and second elongate body members each having a first end to one side of the sinuous member and each having a second end to an opposed side of the sinuous member, wherein, in use, the first ends of the first and second elongate members may be moved towards one another such that the second ends of the first and second elongate members are moved apart, movement of the first and second elongate members being accommodated by flexure of at least a portion of the sinuous member, wherein the portion of the sinuous member that flexes during movement of the first and second elongate body members is shaped to comprise at least one point of inflection.

Preferably, the first ends of the first and second elongate body members form handle portions and the second ends of the first and second elongate body members form clamping portions. Further, the clamping device may be double ended and both first and second ends of the first and second elongate body members form both clamping and handle portions.

The handle portions may be provided on outer edges of the elongate body members and the clamping portions on inner edges.

Preferably, the clamping device is provided as one piece. In particular, the one-piece clamping device is provided as a one-piece moulding.

Preferably, the first and second elongate body members and the sinuous member may be formed from plastics material.

Alternatively, the sinuous member is a shaped metallic element whilst the first and second elongate body members are formed from plastics material.

Most preferably, the sinuous member may be located at a substantially central region of the clamping device and may be, substantially, S'-shaped or Z'-shaped, or mirror images thereof.

Further, the sinuous member may be substantially sinusoidal.

Advantageously, the clamping device may comprise one hinge only, in the form of the sinuous member.

Alternatively, the sinuous member may be shaped to comprise three points of inflection.

The first and/or second ends of the first and second elongate body members may be provided with a pivot point adjacent the one or both sides of the sinuous member.

Preferably, the pivot point(s) may be provided on inner edges of the first and second elongate members as part of, or adjacent, the clamping portions.

At rest, the first and second elongate body members may be urged together so that portions of the first and second elongate body members and/or the pivot point(s) abut, wherein the urging force is provided by the sinuous member.

This may be provided by the sinuous member being pre-loaded during manufacture of the clamping device. As such, various portions of the sinuous member are subjected to compressive or tensile forces whilst at rest.

In use, the first or second ends of the first and second elongate body members are movable together, or apart, from rest positions against a returning force, provided by the sinuous member. The returning force is a reaction force and is provided for returning the first or second ends to their respective rest positions.

In particular, in use, the returning force and the urging force provide an enhanced resistance to opening the clamping device and, consequently, an enhanced clamping force.

Alternatively, portions of the sinuous member may provide, in use, clamping surfaces.

In a further alternative, the elongate body members may form at least part of the sinuous member.

The sinuous member may be provided with a substantially square, rectangular, circular, oval, !Hlshaped or I'-shaped cross-section, or combinations thereof.

Most preferably, the clamping device is a clothes peg.

Advantageously, providing the sinuous member with at least one point of inflection allows for compactness of the sinuous member whilst providing an increased working length of the sinuous member through which stresses during operation are distributed. In particular, this provides a reduced maximum bending stress on the sinuous member which helps to prevent wear and, therefore, increases the working life of the clamping device during normal operating conditions. Further, the gradient of the force deflection curve of the resistance force in operation of the apparatus is less steep providing a flatter force deflection curve.

Thus, the force required to operate the clamping device when the first ends of the first and second elongate members are first pressed together is substantially constant or very similar to, albeit perhaps somewhat less than, the force required throughout further pressing together of the ends and moving apart of the opposed second ends.

Advantageously, providing the clamping device as one piece helps to prevent the clamping device from coming apart or disassembly. Naturally, a one-piece clamping device in the form of a clothes peg is easy to keep clean -as it can be washed because there are no wooden or metal parts -and does not cause staining to clothes, unlike some prior art clothes pegs.

Further, providing the one-piece clamping device as double-ended, orientation of the clothes peg for use is minimised as it may be used from holding it at either end.

Naturally, it will be understood that this will benefit, for example, the visually impaired or those with limited dexterity. Users are also aided by the range of shapes and texturing of the handles achievable through moulding the clamping device.

Throughout the application, a point of inflection is defined as a point on a curve at which the tangent crosses the curve itself. Additionally, this can be defined as a point on a curve at which the curvature changes sign.

Embodiments of the invention will now be described, by way of example only, with reference to, or as shown in, the accompanying drawings, in which: Figure 1 is front view of an embodiment of clothes peg according to the present invention; and Figure 2 is a perspective view of an alternative embodiment of clothes peg according to the present invention.

Figure 3 is a front view of an alternative embodiment of clothes peg according to the present invention; Figures 4 and 5 are front views of further alternative embodiment of clamping device according to the present invention; and Figures 6 and 7 are front views of yet a further alternative embodiment of clamping device according to the present invention.

Figures 1 and 2 show a double-ended, one-piece clothes peg, indicated generally by reference 1. The clothes peg 1 is provided with first and second elongate body members 2,3 and a sinuous member 4, in the form of an lSIshaped member 4. The S'-shaped member 4 is located in a substantially central region of the clothes peg 1 and connects the first and second elongate body members 2,3.

The elongate body members 2,3 are semi-rigid and each have a first end 5 to one side of the sinuous member 4 and each have a second end 6 to an opposed side of the sinuous member 4. Each elongate body member 2,3 is provided with front and rear faces 7,8 and inner and outer edges 9,10.

The inner edges 9 of the elongate body members 2,3 face each other whereas the outer edges 10 do not. The outer edges 10 provide one or more handle portions 11. The handle portions 11 may be, simply, the distal ends of the elongate body members 2,3. Alternatively, the handle portions 11 may be provided as indentations or notches in the outer edges 10 or textured parts of the outer edges 10, which aid gripping the clothes peg 1 by a user. Figure 2 shows an example of a handle portion llA which is provided by texturing the outer edge 10. The inner edges 9 are provided with pivot points 12 adjacent the S'-shaped member 4. In rest, as shown in Figure 1, the elongate body members 2,3 may be in contact through an abutting relationship of the pivot points 12 of each elongate body member 2,3. The pivot points 12 act as fulcra for the body members 2,3. The pivot points 12 do not need to be placed directly adjacent the S'-shaped member 4.

However, positioning of the pivot points 12 adjacent the S'shaped member 4 provides, generally, a lower resistance force to operation of the clothes peg 1. In a preferred embodiment, the pivot points 12 are provided offset from the centre line of the clothes peg 1, as shown in Figure 2. In such an arrangement, an item to be clamped is prevented from ingress and/or entanglement with the S'-shaped member 4 by the pivot point 12 having overlapping portions 12A, 122.

Further, the IStshaped member 4 is protected from damage and/or natural wear which could affect the long term performance of the clothes peg 1.

The inner edges 9 are also provided with jaw portions 13. The jaw portions 13 may be any shape but are, typically, correspondingly-positioned indentations or notches l3A located on the inner edges 9. Additionally, the jaw portions may be provided by undulating surfaces 13B.

The inner edges 9 may also be textured to provide an enhanced grip. In a preferred embodiment, the indentations or notches have a pitch of less that or equal to twice the diameter of a flexible clothes line and, typically, between one and two times the diameter of the clothes line. This feature provides an increased force on a clamped item as the clothes peg is prevented from returning to its rest position -this being the position it would assume if the jaw portions were symmetrical.

The S'-shaped member 4 is spring-like and urges the elongate body members 2,3 in to a rest position in which the elongate body members 2,3 are equally spaced apart at the first and second ends 5,6. The elongate body members 2,3 can rotate about the!SIshaped member 4 and/or the pivot points 12 when an operating force is applied to the clothes peg 1. However, the S'-shaped member 4 provides resistance to rotation (operation of clothes peg) and temporarily stores the spring energy. Once the operating force is removed, the so stored spring energy returns the elongate body members to their respective rest positions. The S'-shaped member 4 is one example of a sinuous member 4 having at least one point of inflection. In Figure 1, the S'-shaped member 4 is oriented vertically inline with the pivot points 12 along the centre line of the clothes peg 1. In Figure 2, the S'-shaped member 4 is oriented at 900 to that of Figure 1. Naturally, it will be understood that a further preferred embodiment of sinuous member 4 is provided by a member shaped as a mirror image of the S'-shaped members shown in Figures 1 and 2. In an alternative embodiment, the!S!shaped member 4 may be an irregular S1 shape. Additionally, portions of the S'-shaped member 4 may be turned-in or turned-out. An example of this is shown in Figure 2 in particular, generally by reference 4A, where an end of the ISlshaped member 4 is turned-in towards the centre of the S'-shaped member 4. In a further embodiment, the sinuous member 4 may have greater than one point of inflection, as would be provided by the sinuous member 4 being sinusoidal, for example. The cross-sectional shape of the sinuous member 4 is substantially rectangular or square, although other cross-sectional shapes, either regular or irregular, provide the same affect. For example, the sinuous member may have a substantially circular cross-section; however, this is likely to be both more difficult to mould and more costly. The length, thickness and/or cross-sectional area of the sinuous member can be varied to optimise the stiffness of the sinuous member 4 and, therefore, the resistance to rotation / operation of the clothes peg 1. Preferably, the sinuous member 4 provides a high degree of stiffness to resist twisting and/or lateral movement of the elongate body members 2,3 during use. Advantageously, as a result, alignment of the elongate body members 2,3 is maintained even following prolonged use of the clothes peg 1 (clamping device). In a preferred embodiment, as shown in Figure 1, the moulding characteristics of the polymer material of S'-shaped member 4 may be utilised to urge the elongate body members 2,3 together whilst in the rest position. Accordingly, in a rest position, the S'-shaped member 4 is pre-loaded, wherein the sinuous member 4 or various portions of the sinuous member 4 are subjected to compressive or tensile forces. Such pre-loading may be imparted during the moulding process. In particular, pre-loading may be imparted by altering the characteristics of the sinuous member, for example, by altering the shape of cross-section of the sinuous member or by altering its thickness. To operate the clothes peg, a user must, therefore, overcome the urging force of the S'-shaped member 4 -provided by pre-loading the S'-shaped member 4 -and the resistance of the S'-shaped member 4 during pivoting of the elongate body members 2,3. As such, an enhanced resistance force to operating the clamping device (clothes peg 1) at one end 5,6 may be provided and, consequently, an enhanced clamping force may be provided at the other end 6,5.

In use, the clothes peg 1 of the present invention is operated by moving, from their rest positions, the first ends 5 towards one another -by pressing the handle portions 11 together between, say, a finger and a thumb. The elongate body members 2,3 are caused to rotate about the S'-shaped member 4 and about the pivot point 12 -located on the first end 5 -against the resistance and/or urging force of the S!shaped member 4. Rotation of the elongate body members 2,3 causes a subsequent moving apart of the second ends 6. In this position, the clothes peg 1 is open and can be placed over an article to be clamped. The S'-shaped member 4 stores the spring energy until the handle portions 11 are released. Once released, the elongate body members 2,3 and first and second ends 5,6 return to their rest positions through the reaction of the -10 -S' -shaped member 4 to removal of the pressing force on the handle portions 11. In particular, the stored spring energy and urging force return the first and second ends to their respective rest positions. In particular, the second ends 6 of the open clothes peg 1 can be placed over an item to be clamped which is already placed over a conventional flexible clothes line. When the pressing force on the handle portions 11 is released, the second ends 6 move together and exert a clamping force on the item to be clamped and the flexible clothes line. In a preferred embodiment, the flexible clothes line is located in one of the indentations or notches 13A or the undulating surfaces 13B. In a further embodiment, pressing together of the first ends 5 to the point that they touch provides a normal maximum opening of the second ends 6 and, therefore, the clothes peg. However, owing to the semi-rigid nature of the elongate body members 2,3 and/or the bendability of the S'-shaped member 4, compliance of those parts to accommodate larger items is provided. When needed, the elongate body members 2,3 and/or the S'-shaped member 4 can flex to provide a greater than normal maximum opening of the second ends.

Figure 3 shows an alternative embodiment of clothes peg according to the present invention but substantially as described in relation to the clothes peg of Figures 1 and 2.

In this embodiment, the sinuous member 4 is substantially sinusoidal and, therefore, comprises numerous points of inflection. The remainder of the clothes peg is substantially as described in relation to Figures 1 and 2.

Figures 4 and 5 show a further alternative embodiment of clamping device 1' according to the present invention.

The clamping device 1' is substantially as described in relation to the clothes peg 1 of Figures 1 and 2; however, -11 -in this embodiment, inner edges 9 and/or parts which provide the pivot points 12' provide clamping surfaces or jaws 13.

In addition, as can be seen in Figure 4 in particular, portions 14 of the sinuous member 4 provide, in use, clamping surfaces l4A,l4B. In this embodiment, it is desirous for an item to be clamped to be able to interact with at least part of the sinuous member 4. Pivot points 12' act, in addition to their pivoting function, as jaws 12' to aid clamping on an item. Figure 4 also shows a clamping device 1' in use where elongate body portions 2,3 at one end 6 have been pressed together, to provide a corresponding widening of the elongate body portions 2,3 at the respective other end 5. The clamping surfaces 14A,l4B have been moved apart and await insertion of an item to be clamped.

Figures 6 and 7 show an alternative embodiment of clamping device 1' of the present invention. The clamping device 1' of Figures 6 and 7 is very similar in operation to the clamping device 1' of Figures 5 and 6. In this embodiment, the elongate body members 2,3 form part of the sinuous member 4' . As such, clamping occurs between parts of the sinuous member 4', as can be seen at references 14A,14B. The pivot points 12' also act as jaws 12' to aid clamping of an item, in use. Naturally, it will be understood that, in this embodiment, the clamping device 1' is an oversized sinuous member 4' . The elongate body portions 2,3 are formed as parts of the sinuous member 4' and provide handles 10 for operation and/or other jaws 13.

Accordingly, an item to be clamped is caught between two parts of the sinuous member. Owing to the shape of the sinuous member 4' shown in Figures 6 and 7, it is clearly discernable that a point of inflection -as defined herein -is provided at or around reference X. Reference X is -12 -provided at the most central point of the clamping device 1', as shown in Figures 6 and 7.

The operating characteristics of the clamping device can be optimised by varying the thickness, length and/or cross-section of the sinuous member, and by varying the distance of the pivot point(s) from the centre line of the sinuous member. Additionally, the operating characteristics are further varied by the choice of material of manufacture and the mechanical properties of the material. In addition, stiffness of the elongate body members can be varied by altering the characteristics of the cross-section of the elongate body member, particularly adjacent the sinuous member, and, so, increase or decrease the amount of compliance.

Preferably, the clothes pegs or clamping devices are manufactured from materials in the group of polyolefins, for example, polyethylene or polypropylene. Additionally, filled-grade polyelefins would provide increased stiffness.

In an alternative, other engineering polymers, such as acetal may be used.

Although the clothes peg is preferably made in one piece by plastics injection moulding, in an alternative embodiment, the S'-shaped member 4 may be a separate metallic element or, even, a separate plastics element provided as an insert moulding or for subsequent assembly.

Providing the!SIshaped member 4 as a separate piece allows for greater variation in the operating characteristics of the clothes peg. However, this advantage is likely to add to the per unit cost of the clothes pegs.

It will be understood that the sinuous member of the present invention will equally find utility in other clamping devices and further variants of clothes pegs. For -13 -example, the sinuous member may be used with a one-ended clothes peg. The clamping devices of the present invention are also suitable for utility as a clamp for closing food bags, as a paper clip or for hanging greeting cards.

Claims

-14 -CLAIMS: 1.) A clamping device comprising first and second

elongate body members and a sinuous member, the sinuous member being located between, and connecting, the first and second elongate body members, the first and second elongate body members each having a first end to one side of the sinuous member and each having a second end to an opposed side of the sinuous member, wherein, in use, the first ends of the first and second elongate members may be moved towards one another such that the second ends of the first and second elongate members are moved apart, movement of the first and second elongate members being accommodated by flexure of at least a portion of the sinuous member, wherein the portion of the sinuous member that flexes during movement of the first and second elongate body members is shaped to comprise at least one point of inflection.

2.) A clamping device as claimed in claim 1, wherein the first ends of the first and second elongate body members form handle portions.

3.) A clamping device as claimed in claim 1 or claim 2, wherein the second ends of the first and second elongate body members form clamping portions.

4.) A clamping device as claimed in any of claims 1, 2 or 3, wherein the clamping device is double-ended and both first and second ends of the first and second elongate body members form both clamping and handle portions.

-15 - 5.) A clamping device as claimed in any one of claims 2 to 4, wherein the handle portions are provided on outer edges of the elongate body members and the clamping portions are provided on inner edges.

6.) A clamping device as claimed in any preceding claim, wherein the clamping device is provided as one piece.

7.) A clamping device as claimed in claim 6, wherein the one-piece clamping device is provided as a one-piece moulding.

8.) A clamping device as claimed in any preceding claim, wherein the first and second elongate body members and the sinuous member are formed from plastics material.

9.) A clamping device as claimed in any one of claims 1 to 5, wherein the sinuous member is a shaped metallic element.

10.) A clamping device as claimed in any preceding claim, wherein the sinuous member is located at a substantially central region of the clamping device.

11.) A clamping device as claimed in any preceding claim, wherein the sinuous member is substantially S'-shaped or Z'-shaped, or mirror images thereof.

12.) A clamping device as claimed in any preceding claim, wherein the sinuous member is substantially sinusoidal.

-16 - 13.) A clamping device as claimed in any preceding claim, wherein the clamping device comprises one hinge only, in the form of the sinuous member.

14.) A clamping device as claimed in any preceding claim, wherein the sinuous member comprises three points of inflection.

15.) A clamping device as claimed in any preceding claim, wherein the first and/or second ends of the first and second elongate body members are provided with a pivot point adjacent the one or both sides of the sinuous member.

16.) A clamping device as claimed in claim 15, when appended to claim 5, wherein the pivot point(s) is/are provided on inner edges of the first and second elongate members as part of, or adjacent, the clamping portions.

17.) A clamping device as claimed in either of claim 15 or claim 16, wherein, at rest, the first and second elongate body members are urged together so that portions of the first and second elongate body members and/or the pivot point(s) abut, wherein the urging force is provided by the sinuous member.

18.) A clamping device as claimed in claim 17, wherein the sinuous member is pre-loaded during manufacture of the clamping device, to provide the urging force.

19.) A clamping device as claimed in claim 18, wherein, at rest, various portions of the sinuous member are subjected to compressive or tensile forces.

-17 - 20.) A clamping device as claimed in any preceding claim, wherein, in use, the first or second ends of the first and second elongate body members are movable together, or apart, from rest positions against a returning force, provided by the sinuous member, for returning the first or second ends to their respective rest positions.

21.) A clamping device as claimed in claim 20, when appended to any of claims 17 to 19, wherein, in use, the returning force and the urging force provide an enhanced resistance to opening the clamping device and, consequently, an enhanced clamping force.

22.) A clamping device as claimed in any preceding claim, wherein portions of the sinuous member provide, in use, clamping surfaces.

23.) A clamping device as claimed in any preceding claim, wherein, in use, an item to be clamped is caught between two parts of the sinuous member.

24.) A clamping device as claimed in any preceding claim, wherein the elongate body members form at least part of the sinuous member.

25.) A clamping device as claimed in any preceding claim, wherein the sinuous member is provided with a substantially square, rectangular, circular, oval, tHlshaped or I'-shaped cross-section, or combinations thereof.

-18 - 26.) A clamping device as claimed in any preceding claim, wherein the clamping device is a clothes peg.

27.) A clamping device substantially as herein described, with reference to the accompanying drawings.