GB2106978A - A fastening for a strap - Google Patents

Abstract

A fastening for a strap, comprising a body 13 having a passage 18 extending therethrough for receiving one or more layers of strap passing through the body and an opening 30 in a lateral wall of the body communicating with the passage and located in such a position on the body with respect to the shape of the passage that it exposes an edge of a strap when such is inserted into the passage, and a strap retaining member 12 insertably into the passage through the lateral opening and operable, when so inserted, to cause a strap in the passage to be restrained against movement longitudinally of the strap with respect to the body of the fastening. <IMAGE>

Description

SPECIFICATION A fastening for a strap The present invention relates to a fastening for a strap, which can be used to retain strap in loops or round packages or the like.

As used in this specification the term "strap" will be understood to refer to any form of band or strip or tape of material of elongate form having two flat parallel faces. One commonly used type of strap is known as webbing.

Webbing strap is used in many applications, in particular for performing restraining functions.

Such webbing strap is used, for example, to secure a child safety seat in a motor vehicle or to form a restraining harness for a child's carricot.

Such strap is also widely used in aircraft cargo holds for cargo retention within the hold. In order to form connections between different lengths of webbing strap, or to secure the webbing strap to fixed anchorage points the webbing is usually supplied either with a stitched eye splice or a buckle stitched to one end. Since a wide variety of shapes and sizes of containers are found within the aircraft cargo hold it is necessary to have a wide range of different strapping elements, and the lack of flexiblity in use of preformed strapping elements in which the buckle or other fastening means are stitched in position constitutes a serious disadvantage.

One attempt to overcome this disadvantage has been made by providing lengths of strap with at least one end unattached, and a separate fastening device in the form of an encircling woggle through the passage in which an end of the webbing can be inserted prior to being passed around a fixed anchorage. The free end of the strap is then inserted again through the opening in the woggle and a wedge-shape securing member is introduced from one end of the passage, longitudinally of the webbing, into the interior to jam the woggle in position once the required tension has been applied to the strap. In order to ensure adequate force is applied to jam the strap it is necessary to use a tool in order to force the wedge into position.For additional security the opposite major faces of the woggle are provided with openings from the edges of which a plurality of teeth project towards the interior of the woggle to grip against the webbing strap securely when the wedge is forced into the woggle.

Although such a device overcomes the disadvantage of the fixed buckle arrangement, of requiring lengths of webbing to be formed to a predetermined length and a buckle stitched on in advance, for example at a factory, it is not possible to release the fastening once made so that the strap has to be cut in order to release the cargo at the end of the voyage. This leads to a consequent wastage of strapping and a lack of economy in use.

The technical problem on which the present invention is based is that of providing a fastening for strap such as webbing strap which, whilst providing a secure fastening to ensure adequate safety, is nevertheless releasable without requiring special tools for breaking or releasing the connection.

According to the present invention a fastening for a strap comprises a body having a passage extending therethrough for receiving one or more layers of strap passing through the body, and an opening in a lateral wall of the body communicating with the passage and located in such a position on the body with respect to the shape of the passage that it exposes an edge of the strap when such is inserted into the passage; and a strap retaining member insertable into the passage through the lateral opening and operable, when so inserted, to cause the strap in the passage to be restrained against movement longitudinally of the strap with respect to the body of the fastening.

Such restraint, of course, can be considered as restraint against relative movement such that the fastening is restrained against movement along the strap if the strap is held between fixed anchoring points.

The strap retaining member may operate to restrain the strap against movement relative to the body by acting as a wedge to press the strap against an inner surface of the passage whilst itself exerting a force possibly through another layer of strap on the opposite inner surface of the passage. It is believed that although satisfactory for light loads, simply wedging the strap into the body will not provide an entirely secure fastening for all purposes, and in the preferred embodiment of the invention the strap retaining member is operable to restrain the strap against movement relative to the body by causing the strap in the passage to follow a closely bounded sinuous path defined by an inner surface of the passage and at least one surface of the strap retaining member.

The above strap retaining member may also be formed so as to apply the above-mentioned wedging action so that the strap within the passage is not only deflected into the sinuous path, but also wedged firmly in this path so that it is held securely against movement with respect to the body.

To define this sinuous path the passage in the body preferably has at least one inner surface constituted by a plurality of part-cylindrical surfaces the axes of which lie parallel to one another and transverse the length of the passage.

Such part-cylindrical surfaces may be concave or internal cylindrical surfaces, although alternatively they may be convex or external cylindrical surfaces. Preferably the sinuous path includes at least one acute angle change in direction defined by a sharp edge or corner. Of course, the strap retaining member must have an outer surface which is complementary to that of the passage, and in the embodiment referred to above the outer surface of the strap retaining member is preferably constituted by a corresponding plurality of partcylindrical surfaces which, when the strap retaining member is inserted into the passage through the lateral opening, lie parallel to the part cylindrical surfaces of the passage to define the sinuous path of the strap.

These part-cylindrical surfaces of the strap retaining member preferably constitute the surfaces of a body portion for defining one side of the sinuous path of the strap, and the strap retaining member is also provided with an enlarged head portion which joins the body portion at a shoulder.

In the preferred embodiment of the invention the lateral opening includes an enlarged mouth part for receiving the heat portion of the strap retaining member. Such head portion of the strap retaining member may project from the mouth of the lateral opening when the strap retaining member is inserted into the passage, whereby to provide a grip for removal of the strap retaining member from the passage to allow withdrawal of the strap from the fastening when desired.

Alternatively, however, the head of the strap retaining member may be of such a size that it lies flush with the side wall of the body once thq strap retaining member has been inserted into the passage, whereby to inhibit removal of the strap retaining member from the body and to provide an effectively permanent fastening.

In order to facilitate insertion of the strap retaining member into the passage, particularly when two layers of strap are present, the body portion of the strap retaining member preferably has a wedge shape leading end portion remote from the head portion terminating in achise.l-like edge at the end remote from the head portion.

One embodiment of the present invention will now be more particularly- described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is'a perspective view of the embodiment mounted on two layers of webbing strap; Figure 2 is a perspective view, on an enlarged scale, of the fastenmg-showing the parts separated fram one another; Figure 3 is a side view in the direction of the arrow B of Figure 2; and - Figure 4 is an end view in the direction of the arrow A of Figure 2.

Referring now to the drawings the strap fastening is shown comprises a body, generally indicated 11 and a strap retaining member generally indicated 1 2. The body is of generally rectangular form and has an upper major face 13 and a lower major face which cannqt be seen in the drawings. The terms "upper"- and "lower" are used in this description merely to define the orientation in which the fastening is illustrated, and it wilt be appreciated that such terms are not intended-to be construed as limitative on the device. [ndeed, the device is entirely free from restrictions as to the orientation in which it can be used, this being determined in.practice by the direction in which the strap on which it is mounted needs to lie in drder to fulfil its intended function.

The body 11 has two parallel end walls 14, 1 5 and two side walls 16, 1 7. Passing through the body between the end walls 14, 1 5 is an internal passage 1 8 which extends right through the body 11. The width of this passage determines the maximum width of webbing strap which can be used with the fastening although strap which is narrower than this maximum may also be employed.

In the side walls 16 there is an opening 30 which opens into the side of the passage 18. In the vicinity of this opening 30 the surface of the passage 1 8 is defined by two inter-penetrating transverse cylindrical surfaces 19, 20 the axes of which extend orthogonally with respect to the length of the passage 1 8. A further opening 21 may be provided in the opposite side wall 1 7 of the body 11 although in other embodiments such opening is not provided for reasons which will-be discussed below.

The strap retaining member 12 has a body portion 22 and a head portion 23. The body portion comprises two generally cylindrical elements 24, 25 Ining parallel to one another and interconnected by a web 26 lying in the plane defined by the two parallel axes of the cylindrical portions 24, 25. The head portion 23, from which the body portion 22 prdjects:has a cross-sectional shape corr sponding to that of the opening 30.

The strap fastening device described above operates as follows: A length strap to be fastened is passed through-a passage 18 from one end to the other, for example, by introducing it into the passage 1 8 through the opening in the end wall 15 and passing it out through the opening in the end wall 14. The free end of the sfrap is then passed around the container and or anchor point to which it is desired to secure the strap, and the free end is then passed back through the passage 1 8 by introducing it first through the opening in the end wall 14 and passing it out through the end wall 15.In the majority of cases the two sections of strap extending out from each end wall 14. 1 5 will diverge away from one another as illustrated in Figure 3, and-this will cause the parallel lengths of strap within the passage 1 8 to be spaced slightly from one another since the dimension of the passage 1 8 at the entrance and exit thereof at the walls 14, 1 5 substantially greater than twice the thickness of the strap, for example in the region of three to four times the thickness of the strap.As viewed through the opening 30 in the side wall 16, them fore, the two lengths of strap within the passage 1 8 are spaced from one another thereby facilitating insertion of the end of the body portion 22 of the strap retaining member 12 which, as can be seen in Figure 2, has a chisel edge for this purpose. The strap retaining member 1 2 is inserted through the opening 30 in the side wall 1 6 whilst the strap is held under tension and consequently forces the length of strap closely to follow the part-cplindrical surfaces defining the opposite walls of the. passage 1 8 to follow the sinuous path defined by these surfaces. In particular the sinuous path of the strap includes a sharp bend over the edges 27, 28 which constitute the crests of the opposite inner surfaces of the passage 18 where the part cylindrical surfaces 1 9, 20 meet.

Because the strap retaining member 12 is inserted laterally of the strap it can be fitted using a force not greater than that which can readily be applied manually, and once fitted will secure the strap within the body 11 against tensions due to the clamping and flexing of the strap. Release of the fastening can also be achieved readily simply by gripping the exposed part of the head portion 23 and drawing it out laterally of the strap.

Should it be required to make non-releasable fastenings, it is only necessary to ensure that the length of the head portion 23 (that is the dimension parallel to the axes of the cylindrical body portions 24, 25) is not greater than the corresponding length of the opening 30 between the side wall 1 6 and an abutment surface 29 defined by the ends of the part-cylindrical surfaces 19, 20 (see Figure 2). Thus when such strap retaining member 12 is inserted through the opening 30 the head 23 will lie flush with the side wall 1 6 presenting no surface which can be gripped for removal. The fastening is then effectively permanent since it cannot be released without special action on the retaining member 12 such as by driving it out from the opposite side wall 17.If this side wall is closed (and it is such embodiments in which the optional opening 21 would not be provided) then release of the fastening by removal of-the strap retaining member 12 is effectively prevented.

A fastening of the invention thus provides a simple means for effecting secure connection between two layers of strap.

Using the same principle, a fastening for securing a single layer of strap in circumstances --where such is required, for example if the body portion 11 were to form part of a fixed anchoring, may be achieved simply by ensuring that the dimensions of the two cylindrical parts 24, 25 of the body portion 22 of the strap retaining member 12 are such as to occupy the transverse part of the passage leaving only sufficient space for the single layer of strap. Alternatively, if the embodiment described with reference to the drawings is the only one available, a dummy length of strap may be inserted into the passage 1 8 prior to insertion of the strap retaining member 12.

Claims (12)

1. A fastening for a strap, comprising a body having a passage extending therethrough for.

-receiving one or more layers of strap passing through the body and an opening in a lateral wall of the body communicating with the passage and located in such a position on the body with respect to the shape of the passage that it exposes an edge of a strap when such is inserted into the passage, and a strap retaining member insertable into the passage through the lateral opening and operable, when so inserted, to cause a strap in the passage to be restrained against movement longitudinally of the strap with respect to the body of the fastening.

2. A fastening as claimed in Claim 1, in which.

the strap retaining member is operable to restrain the strap against movement relative to the body by acting as a wedge to press the strap against an inner surface of the passage whilst itself exerting a force on the opposite inner surface of the passage.

3. A fastening as claimed in claim 1 or claim 2, in which the strap retaining member is operable to restrain the strap against movement relative to the body by causing the strap in the passage to follow a closely bounded sinuous path defined by an inner surface of the passage and at least one surface of the strap retaining member.

4. A fastening as claimed in claim 3, in which the passage has at least one inner surface constituted by a plurality of part-cylindrical surfaces, the axes of which lie parallel to one another and transverse the length of the passage.

5. A fastening as claimed in claim 4, in which the said part-cylindrical surfaces are internal cylindrical surfaces.

6. A fastening as claimed in claim 4 or claim 5, in which the strap retaining member has an outer surface constituted by a corresponding plurality of part-cylindrical surfaces which, when the strap retaining member is inserted into the passage through the lateral opening, lie parallel to the partcylindrical surfaces of the passage to define the sinuous path for the strap.

7. A fastening as claimed in any of claims 3 to 6, in which the strap retaining member has a body portion for retaining one side of the sinuous path of the strap and an enlarged head portion which joins the body portion at a shoulder.

8. A fastening as claimed in claim 7, in which the lateral.opening includes an enlarged mouth part for receiving the head portion of the strap retaining member.

9. A fastening as claimed in claim 8, in which the head of the strap retaining member projects from the mouth of the lateral opening when inserted into the passage to provide a grip for removal from the passage to release the strap from the fastening.

10. A fastening as claimed in claim 8, in which the head of the strap retaining member is flush with the side wall of the body once inserted whereby to inhibit removal from the body and provide an effectively permanent fastening.

11. A fastening as claimed in any of claims 7 to 10, in which the body portion of the strap retaining member has a chisel-like wedge-shape leading end portion remote from the head portion to facilitate insertion of the strap retaining member between two adjacent layers of strap in the passage in the body entering through the lateral opening in the body.

12. A fastening for a strap substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.