AU2003203691B2

AU2003203691B2 - Fall arrest safety devices

Info

Publication number: AU2003203691B2
Application number: AU2003203691A
Authority: AU
Inventors: Richard Hugh MILLAR
Original assignee: BEAVER BRANDS Pty Ltd
Current assignee: Bunzl Brands & Operations Pty Ltd
Priority date: 2003-04-15
Filing date: 2003-04-15
Publication date: 2009-05-21
Anticipated expiration: 2023-04-15
Also published as: AU2003203691A1

Description

Regulation 3.2 Revised 2/98 AUSTRALIA Patents Act, 1990 ORIGINAL COMPLETE SPECIFICATION TO BE COMPLETED BY THE APPLICANT NAME OF APPLICANT: Beaver Sales Pty Limited ACTUAL INVENTOR: Richard Hugh Millar ADDRESS FOR SERVICE: Peter Maxwell & Associates Level 6 60 Pitt Street SYDNEY NSW 2000 INVENTION TITLE: FALL ARREST SAFETY DEVICES DETAILS OF ASSOCIATED APPLICATION NO(S) Nil The following statement is a full description of this invention including the best method of performing it known to us: m:\docs\20031002\031779.doc IP Australia Documents were received on: 5APR 2003 Batch No: 2 The present invention relates to fall arrest safety devices for protecting persons operating with safety lines at elevated locations. In particular, the invention relates to a device for preventing a fall arresting lanyard line interfering with the spring locking operation of a double lock safety hook device 5 that interconnects the lanyard line to, say, a D-ring of a harness worn by such persons. Fall arresting lanyard lines typically have a closed loop formed at one or both of their ends for engaging through an eye of an eye defining ring portion of a double lock safety hook device. The device also has a hook portion, the 10 open loop of which is normally closed by a spring acting hook latch. As the hook portion engages a D-ring of the harness, the closure of the open loop by the spring acting hook latch must be reliable and must only be openable when desired, normally by the person wearing the harness. To ensure that the spring acting hook latch is not inadvertently forced 15 open, say, by pressure applied against the hook latch by the D-ring itself, the device also has a spring acting lock latch, the operation of which controls whether the hook latch can be forced open or not. The lock latch may be moved by finger pressure against the pressure exerted by a spring from a first position, where it provides a reliable impediment to opening of the hook latch, 20 to a second position, where it no longer provides any impediment to opening of the hook latch. The release of finger pressure against the lock latch causes the lock latch to spring back to its first position. It has recently been found that the closed loop of the lanyard line engaging through the eye of the eye defining ring portion of the device may 25 slide into a position where it urges against the lock latch and, in certain circumstances, may even move the lock latch from its first position to its 21/04/09 3 second position, whereupon the safety of the harnessed worker would be put at great risk if the hook latch were to be inadvertently opened. Such interference in the spring locking operation of the device by the lanyard line is undesirable, and it is an object of the present invention to 5 address this problem by providing a keeper for the lanyard line, the keeper being so disposed on the double lock safety hook device that it provides a barrier to the closed loop of the lanyard line moving to a position where it interferes with the spring locking operation of the device. In one form of the invention, there is provided a keeper for a lanyard line 10 engaged to a double lock safety hook device, the keeper comprising a sheath portion adapted to be secured to an eye defining ring portion of the device, and at least one barrier forming portion projecting from the sheath portion adapted for preventing a closed loop at an end of the lanyard line that is engaged through the eye of the eye defining ring portion moving against a lock 15 latch of the device. In another form of the invention, there is provided a double lock safety hook device and keeper assembly, wherein the device comprises a body, a hook portion extending from a first end of the body, a hook latch which closes the hook portion in normal operation of the device but is openable by a user, a 20 lock latch which is movable by the user between a first position, where it provides an impediment to opening of the hook latch, and a second position, where it no longer provides an impediment to opening of the hook latch, an eye defining ring portion extending from a second end of the body, through the eye of which a lanyard line is adapted to be engaged, and wherein the keeper is 25 disposed on the eye defining ring portion so that it provides a barrier to movement of the lanyard line to a position where it urges against the lock latch. 21/04/09 4 Preferably, the keeper is formed in two parts that are adapted to be fitted together for securing to the eye defining ring portion. It is preferred that each of the two parts of the keeper include an open channel portion, wherein the fitting together of the two parts defines a closed 5 channel through which the eye defining ring portion is adapted to be located. In a preferred form, there are two barrier forming portions projecting from opposed sides of the sheath portion. The two parts of the keeper are preferably snap fitted together by the frictional interengagement of male and female members disposed on opposed 10 parts of each barrier forming portion. Preferably, the two barrier forming portions are integrally connected to the sheath portion and are bulb-shaped. In the assembly, the hook latch preferably closes the hook portion by the action of a first spring. 15 It is preferred that the impediment to opening of the hook latch when the lock latch is in the first position is provided by a notch portion formed through the lock latch, in which notch portion a runner pin of the lock latch is located. In a preferred form, the notch portion opens to a track formed through the lock latch, wherein movement of the lock latch to the second position 20 allows the runner pin to exit the notch portion and enter the track, whereupon the hook latch may be opened by the user, during the opening of which the runner pin travels along the track. The hook latch is preferably pivotally mounted to the body, and the track is arcuately shaped to accommodate the travel path of the runner pin during 25 the opening of the hook latch. Preferably, the lock latch is movable from the first position to the second position against the action of a second spring. 21/04/09 5 It is preferred that the lock latch is pivotally mounted to the body, and the body includes a depression into which the lock latch pivots when moved to the second position. In order that the invention may be more readily understood and put into 5 practical effect, reference will now be made to the accompanying drawings, in which: Fig 1 is a perspective view of a lanyard line that is engaged to a double lock safety hook device and keeper assembly according to a preferred embodiment of the invention, 10 Fig 2 is a plan view of the assembly shown in Fig 1, Fig 3 is an internal plan view of a first part of the two parts of the keeper used in the assembly shown in Fig 2, and Fig 4 is a side view of the first part of the keeper shown in Fig 3. A conventional lanyard line 10 has a pair of closed loops 12, 14 formed 15 at respective ends thereof, each of which are engaged through an eye 15 of an eye defining ring portion 16 extending from one end of a body 17 of a respective steel alloy double lock safety hook device 18a, 18b. Removably secured to the eye defining ring portion 16 of each device 18a, 18b is a keeper 20 for the lanyard line 10. 20 Each device 18a, 18b has a hook portion 22 extending from another end of the body 17, the open loop 24 of which is normally pivotally closed by a spring acting hook latch 26. A harnessed worker is adapted to be connected to an end of the lanyard line 10 via a D-ring of the harness (not shown) being engaged through the hook portion 22 of one of the devices 18a. The device 25 18b at the other end of the lanyard line 10 is adapted to be engaged to, say, a mobile anchorage apparatus on a fixed lifeline safety track. 21/04/09 6 The device 18a has a spring acting lock latch 28 to control the operation of the hook latch 26. The lock latch 28 is pivotable about a pin 30 in the direction of arrow A normally by finger pressure applied to a grooved surface portion 32 thereof and against pressure exerted by an internally mounted coil 5 spring 34. The lock latch 28 is shown in Fig 2 in a first position, prior to being pivoted in the direction of arrow A, where it provides a reliable impediment to pivotal opening of the hook latch 26. The body 17 includes a depression or cut-away section to accommodate the pivotal motion of the lock latch 28. 10 There is a slot 36 formed through the lock latch 28 which engages a runner pin 38 mounted across the hook latch 26. The slot 36 has a track portion 37 and a recess or notch portion 40 opening into the track portion 37. When the lock latch 28 is in the first position, the runner pin 38 is located in the notch portion 40 of the slot 36, the notch portion 40 being so laterally 15 disposed with respect to the track portion 37 that it provides a physical barrier to pivotal movement of the hook latch 26. When the lock latch 28 is pivoted to a second position in the direction of arrow A sufficient to cause the runner pin 38 to exit the notch portion 40 and enter the track portion 37, the hook latch will be free to pivotally move about its pivot pin 42 by finger pressure applied to 20 a grooved surface portion 44 thereof and against pressure exerted by an internally mounted coil spring 46. This will enable the D-ring to be engaged to, or disengaged from, the hook portion 22. Release of finger pressure from the lock latch 28 and hook latch 26 will allow them to spring back to their first position and closed position respectively. 25 The keeper 20 is preferably fabricated of polypropylene treated with a UV inhibitor in a single cavity mould manufacturing process. 21/04/09 7 The keeper 20 comprises two identical keeper parts 22a, 22b, one of which is shown in detail in Figs 3 and 4. When interconnected, the two keeper parts 22a, 22b form a sheath portion 48 (from the coupling together of respective sheath halves 48a) and a pair of barrier forming bulb portions 50, 5 52 (from the coupling together of respective bulb halves 50a, 52a), which integrally project from opposed sides of the sheath portion 48. The sheath portion 48 is thus adapted to surround a large part of the eye defining ring portion 16 to which it is removably secured. Each keeper part 22a, 22b includes an open channel portion 54 wherein 10 the interconnection of the keeper parts 22a, 22b defines a closed channel through which the eye defining ring portion 16 is locatable. The keeper parts 22a, 22b are interconnected by a snap fit provided by the frictional interengagement of male and female members 56, 58 respectively disposed on opposed parts of each barrier forming bulb portion 50, 52. The 15 barrier forming bulb portions 50, 52 are adapted to prevent the closed loop 12 at an end of the engaged lanyard line 10 moving against the lock latch 28 of the device 18a which, as mentioned earlier, may put the safety of the harnessed worker at great risk. Various modifications may be made in details of design and 20 construction without departing from the scope or ambit of the present invention. 21/04/09

Claims

1. A keeper for a lanyard line engaged to a double lock safety hook device, the keeper comprising a sheath portion adapted to be secured to an eye defining ring portion of the device, and at least one barrier forming portion projecting from the sheath portion adapted for preventing a closed loop at an end of the lanyard line that is engaged through the eye of the eye defining ring portion moving against a lock latch of the device.

2. The keeper of claim 1 wherein the keeper is formed in two parts that are adapted to be fitted together for securing to the eye defining ring portion.

3. The keeper of claim 2 wherein each of the two parts of the keeper include an open channel portion, wherein the fitting together of the two parts defines a closed channel through which the eye defining ring portion is adapted to be located.

4. The keeper of any one of claims 1 to 3 wherein there are two barrier forming portions projecting from opposed sides of the sheath portion.

5. The keeper of claim 2 wherein the two parts of the keeper are snap fitted together by the frictional interengagement of male and female members disposed on opposed parts of each barrier forming portion.

6. The keeper of claim 4 wherein the two barrier forming portions are integrally connected to the sheath portion and are bulb-shaped. 21/04/09 9

7. A double lock safety hook device and keeper assembly, wherein the device comprises a body, a hook portion extending from a first end of the body, a hook latch which closes the hook portion in normal operation of the device but is openable by a user, a lock latch which is movable by the user between a first position, where it provides an impediment to opening of the hook latch, and a second position, where it no longer provides an impediment to opening of the hook latch, an eye defining ring portion extending from a second end of the body, through the eye of which a lanyard line is adapted to be engaged, and wherein the keeper is according to any one of claims 1 to 6 and is disposed on the eye defining ring portion so that it provides a barrier to movement of the lanyard line to a position where it urges against the lock latch.

8. The device and keeper assembly of claim 7 wherein the hook latch closes the hook portion by the action of a first spring.

9. The device and keeper assembly of claim 7 or claim 8 wherein the impediment to opening of the hook latch when the lock latch is in the first position is provided by a notch portion formed through the lock latch, in which notch portion a runner pin of the lock latch is located.

10. The device and keeper assembly of claim 9 wherein the notch portion opens to a track formed through the lock latch, wherein movement of the lock latch to the second position allows the runner pin to exit the notch portion and enter the track, whereupon the hook latch may be opened by the user, during the opening of which the runner pin travels along the track. 21/04/09 10

11. The device and keeper assembly of claim 10 wherein the hook latch is pivotally mounted to the body, and the track is arcuately shaped to accommodate the travel path of the runner pin during the opening of the hook latch.

12. The device and keeper assembly of any one of claims 7 to 11 wherein the lock latch is movable from the first position to the second position against the action of a second spring.

13. The device and keeper assembly of any one of claims 7 to 12 wherein the lock latch is pivotally mounted to the body, and the body includes a depression into which the lock latch pivots when moved to the second position. Dated this 21 day of April 2009 Beaver Brands Pty Limited Patent Attorneys for the Applicant PETER MAXWELL & ASSOCIATES 21/04/09