GB2411688A

GB2411688A - Pivoted jaw clamp supporting a hook

Info

Publication number: GB2411688A
Application number: GB0404984A
Authority: GB
Inventors: Thomas Christopher Neil
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-03-05
Filing date: 2004-03-05
Publication date: 2005-09-07
Anticipated expiration: 2024-03-05
Also published as: GB2411688B; GB0404984D0

Abstract

A clamp, particularly for fastening safety netting via a hook (16) to structural building elements such as an I-beam (20), comprises a jaw (10) having a pair of portions (11, 12) spaced apart to define a mouth (13), and an arm (14) pivotally mounted to one of the jaw portions and carrying the hook (16). The arm (14) will be pivoted, either under the weight of e.g. netting engaged on the hook (16) or by an actuator (19), to move its end towards the other jaw portion, in a clamping action. The end of the arm (14) can have a serrated or resilient gripping portion.

Description

241 1 688 Clamn This invention relates to a clamp in more particularly but

not solely to a clamp for fastening safety netting to structural building elements.

Health and Safety Regulations require safety netting to be fitted on building sites in situations where personnel are working above a certain height. Typically, a safety net is securely fastened at its corners to an I-section structural beam using s-shaped hooks. Further s-shaped hooks are arranged at intervals to engage the side edges of the safety net.

A disadvantage of this arrangement is that the S-shaped hooks can readily detach from the I-section beam. A further disadvantage is that the hooks have a tendency to slide down inclined beams.

We have now devised a clamp which elevates the above mentioned problems.

In accordance with this invention, there is provided a clamp comprising a jaw having a pair of portions which are spaced apart to define a mouth, an arm pivotally mounted intermediate its opposite ends to one of the jaw portions for pivotal movement about an axis extending perpendicular to the mouth to cause a first end of the arm to extend into the mouth, the other end of the arm carrying hook means.

In use, the clamp can be used to fasten safety netting to a structural building element such as an I-section beam by positioning the mouth of the jaw around a portion of the beam.

Safety netting can then be attached to the hook means on the arm of the clamp. The weight of the net as well as tensional forces tend to pull the end of the arm carrying the hook means away from the jaw, thereby causing the opposite end of the arm to pivot into the mouth of the jaw to grip the beam.

In this manner, the clamp cannot become detached from the beam because the beam is securely gripped between the arm and one portion of the jaw. This also prevents the clamp from sliding along an inclined beam.

In some instances, it may be desirable to permanently, fasten the clamp in place, for example on vertical or steeply I inclined beams. Accordingly, the clamp preferably further comprises means for biassing said first end of the arm into the i mouth.

Preferably an actuator is attached one end of the arm remote from the point at which the arm is pivoted to the jaw portion, the actuator being operable to apply a force to the arm to cause rotation of the arm into the mouth of the jaw.

10Preferably the actuator comprises a threaded shaft which can be rotated, for example using a spanner, to cause rotation of the arm into the mouth of the jaw.

Preferably the hook means is pivotally mounted to the arm.

15Preferably the first end of the arm is serrated or comprises a portion of an elastomeric or other resiliently deformable material.

An embodiment of this invention will now be described by way of an example only and with reference with accompanying drawings, in which Figure 1 is a side view of a clamp in accordance with I this invention; and Figure 2 is a side view of the clamp of Figure 1, when in use.

25Referring to Figure 1 of the drawings, there is shown a clamp comprising a jaw 10 having a pair of outwardly extending portions 11, 12 which are spaced apart to define a mouth 13 of the clamp. An elongate arm 14 is pivotally mounted intermediate its opposite ends at 15 to one of the jaw portions 12 for pivotal movement about an axis extending perpendicular to the mouth 13. The upper end of the arm 14 is pivotal into the mouth 13 and a hook 16 is pivotally mounted to the other end of the arm 14 on the opposite side of the pivot point 15.

An elongate externally screw-threaded bolt 17 having a head 19 extends through an aperture formed in a rear wall of the jaw 10. The outer end of the bolt 17 engages an internally screw-threaded aperture which extends radially through a shaft 18, which is pivotally attached to the upper end of the arm 14 for rotation about an axis which extends parallel to and radially outwardly of the axis of rotation of the arm 14.

Referring to Figure 2 of the drawings, in use the mouth 13 of the jaw 10 the clamp is fitted onto a portion 20 of an I-section structural beam. The bolt 17 is then rotated to cause the shaft 18 to move along the bolt 17 towards the head 19 of the bolt. This causes the arm 14 to rotate in a clockwise direction as shown about the pivot point 15, thereby causing the upper end of the arm 14 to pivot into the mouth 13 of the jaw 10.

The bolt 17 is rotated until the I-section beam portion 20 is securely gripped between the upper end of the arm 14 and the upper portion 11 of the jaw. It will be appreciated that once the clamp has been fastened in this manner, the clamp cannot readily be detached from the I-section beam 20. Also, it is not possible for the clamp to readily slide along the beam 20.

Safety netting (not shown) can then be engaged with the hook 16, which is pivotally attached to the lower end of the arm 14.

In an alternative embodiment, the bolt 17 and shaft 18 can be omitted. In this embodiment, the upper end of the arm 14 rotates in the clockwise direction under the force of gravity acting on the hook 16. In this manner, the clamp can temporarily hold itself in place on a beam until the safety netting is fitted. The forces applied by the netting to the hook 16 further serve to increase the grip of the clamp on the I-section beam.

A clamp in accordance with this invention is relatively simple in construction, yet provides a reliable and convenient way of attaching safety netting to structural building elements.

Claims

Claims 1. A clamp, comprising a jaw having a pair of portions which are

spaced apart to define a mouth, and an arm pivotally mounted intermediate its opposite ends to one of the jaw portions for pivotal movement about an axis perpendicular to said mouth to cause a first end of said arm to extend into said mouth, the opposite end of said arm carrying hook means.
2. A clamp as claimed in claim 1, arranged so that weight applied to said hook means causes said arm to pivot so that its said first end moves towards the second of said jaw portions.
A clamp as claimed on claim 1, further comprising biassing means for pivoting said arm to move its said first end toward the second of said jaw portions.
4. A clamp as claimed in claim 3, in which said biassing means comprises an actuator which is engaged to said arm at a point remote from its point of pivot to said one jaw portion, said actuator being operable to cause rotation of said arm so that its first end extends into said mouth.
5. A clamp as claimed in claim 1, in which said actuator comprises a threaded shaft.
6. A clamp as claimed in any preceding claim, in which said hook means is pivotally mounted to said arm.
A clamp as claimed in any preceding claim, in which said first end of said arm is serrated.
8. A clamp as claimed in any one of claims 1 to 6, in which said first end of said arm is provided with an element of resiliently deformable material.
9. A clamp substantially as herein described with reference to the accompanying drawings.