TETHERING APPARATUS AND INERTIA LOCKING REEL

Abstract: A tethering apparatus (14) including a harness (15), an anchor (16) and a line member (17) wherein said line member (17) connects said harness (15) to said anchor (16), further including a spool (19) about which the line member (17) is wound, said spool (19) having an inertia lock (18) for arresting the spool (19) when the line member (17) is unwound from the spool (19) at a rate above a predetermined value. The inertia lock (18) preferably includes a housing having an inner surface in the form of a ratchet (32), and a pawl (37) mounted for rotation about an axis substantially parallel to and offset from the axis about which the spool (19) rotates and wherein said pawl (37) is biased to a disengaged condition where the pawl (37) is disengaged from the ratchet (32) and wherein said pawl (37) engages the ratchet (32) and arrests the spool (19) when the line member (17) is unwound from the spool (19) at a rate above a predetermined value.

Description: TETHERING APPARATUS AND INERTIA LOCKING REEL The present invention relates to a tethering apparatus and to an inertia locking reel. The present invention, in so far as it relates to a tethering apparatus, has particular but not exclusive application to tethering apparatus which may be used to tether a fisherman to rocks from which he or she may be fishing. However, it will be appreciated that the invention could also be used in other applications such as for tethering a workman to a ladder, scaffolding or roof to limit fall, for otherwise tethering a person or object to a fixture to limit accidental fall or dropping, or for tethering a yachtsman to a fixture on a yacht. A variety of other applications will be apparent for the use of the tethering apparatus of the present invention. Fishing from rocky shorelines is a popular sport. In many instances at least some of the rocks are covered with marine life including algae. As a consequence the rocks may be slippery, particularly when wet, and wherein there always exists the danger that persons moving about over the rocks may slip and fall into the sea. Many fishermen also fail to observe tide changes and, as a consequence, have been swept into the sea. Workmen working at height require safety equipment to limit falls. In roofing applications guard rails are often erected around the perimeter of the roof so that in the event of a fall the fallen workman will be stopped by the guard rail and prevented from falling further. Alternatively, and in applications where guard rails are impractical the workman may be tethered to a fixture on a roof, ladder or scaffolding. Such tethers generally have a fixed length of rope which must reach its full length prior to arresting the fall of the workman. As a result injury may occur to the workman prior to, or as a result of, the sudden arrest of the fall. In order to minimise this risk, only short tethering ropes may be used. We have now found a tethering apparatus which incorporates an inertia lock so as to almost instantly arrest the fall of a person or object. According to a first aspect of the present invention there is provided a tethering apparatus including a harness, an anchor and a line member wherein said line member connects said harness to said anchor, further including a spool about which the line member is wound, said spool having an inertia lock for arresting the spool when the line member is unwound from the spool at a rate above a predetermined value. According to a preferred embodiment of the first aspect of the present invention there is provided a tethering apparatus including a harness, an anchor and a line member wherein said line member connects said harness to said anchor, further including a spool about which the line member is wound, said spool having an inertia lock wherein the inertia lock includes a housing having an inner surface in the form of a ratchet, and a pawl mounted for rotation about an axis substantially parallel to and offset from the axis about which the spool rotates and wherein said pawl is biased to a disengaged condition where the pawl is disengaged from the ratchet and wherein said pawl engages the ratchet and arrests the spool when the line member is unwound from the spool at a rate above a predetermined value. In a second aspect, we have now found an inertia lock which is of simple construction but provides an effective inertia lock suitable for a variety of applications. According to this aspect there is provided an inertia lock for a spool of wound line member including a housing having an inner surface in the form of a ratchet, and a pawl mounted for rotation about an axis substantially parallel to and offset from the axis about which the spool rotates and wherein said pawl is biased to a disengaged condition where the pawl is disengaged from the ratchet and wherein said pawl engages the ratchet and arrests the spool when the line member is unwound from the spool at a rate above a predetermined value. The harness may be any convenient shackle or fastener which may be attached to the person or object to be tethered. In respect of a harness for a person, suitable the harness may be in the form of an article of clothing such as a pair of trousers, a pair of shorts, a jacket or a shirt. Alternatively the harness may be in the form of a belt. In applications such as for fishermen or other users in the vicinity of water the harness may be in the form of a life jacket or buoyancy vest. The configuration of the harness preferably allows the line member to trail behind the user. However, in certain applications, the harness may be arranged such that the line member extends outwardly in front of the user. Suitable harnesses for objects include any fixture which can be attached to the object without causing substantial damage to the object. Preferably the harness is releasable such that when the tethering apparatus is no longer required the harness may be removed and reused. The anchor may be any convenient configuration adapted to engage a fixture from which Jhe person or object is to be tethered. The anchor may be one or more hooks, karabiners or other anchors adapted to engage with various fixtures. The anchor may be a shackle which in use may be selectively attached to a rail or line member such as may have been erected specifically as an anchorage for rock fishermen and the like. Alternatively, the anchor may be one or more ground engaging members, such as a plurality of spikes which may be selectively driven into the ground or may include one or more fasteners which are specifically designed to expand so as to fill a void, such as a crack or crevice found in a rock formation. A variety of mountaineering equipment may be used to provide suitable anchors, The line member is preferably a flexible member such as a rope, cable or the like. In the second aspect of the present invention the line member may preferably be a belt such as a seat belt. The tethering apparatus includes a spool for storing or gathering selected portions of the line member which may not be required thereby enabling users to alter the extended or operative length of the line member and in turn the distance separating the anchor and the harness. Preferably the spool is attached to or associated with the harness such that it is carried by the person or object. However it will be appreciated that in other embodiments the spool may be attached to, or located near by, the anchor. The spool may provide a cylinder on which the line member may be wound. The spool is preferably operatively connected to return mechanism. Suitable return mechanisms may include manual operable returns such as handles drivingly connected to the spool for rotation, motor driven returns and biasing means, such as a coiled spring, whereby the spool is urged to rotate in a direction which will gather the line member around the spool. The tethering apparatus of the first embodiment of the present invention includes an inertia lock which when operatively engaged prevents, or at least resists, the unfurling of portions of the line member wound on the spool. The inertia lock may be actuated automatically, such as in response to unintentional changes in the user's position which may arise as a consequence of a fall. The locking means may be actuated should the harness' velocity relative to the anchor exceed a predetermined value, which may occur if the person or object falls or is being swept away by a body of water. The inertia lock may be set to actuate when the line member is unwound from the spool at a rate above a predetermined value which corresponds to the action the tethering apparatus is designed to arrest. Changes to the angle of inclination of the inertia lock may increase the sensitivity of the inertia lock and reduce the predetermined rate at which the spool is arrested. The inertia lock may also include facilities enabling the user to override the automatic locking means so as to selectively prevent the automatic actuation of same. In the preferred embodiment of the first aspect of the present invention and in the second aspect of the present invention the inertia lock includes a housing having an inner surface in the form of a ratchet, and a pawl mounted for rotation about an axis substantially parallel to and offset from the axis about which the spool rotates and wherein said pawl is biased to a disengaged condition where the pawl is disengaged from the ratchet and wherein said pawl engages the ratchet and arrests the spool when the line member is wound from the spool at a rate above a predetermined value. The housing has an inner surface in the form of a ratchet. It is not narrowly critical as to the configuration of the ratchet other than it engages the pawl and arrests the spool when the line member is wound from the spool at a rate above a predetermined value. In a preferred embodiment, the housing has " inner surface which is substantially cylindrical and includes a plurality of teeth to form the ratchet. Alternatively, the ratchet may be provided on the inner surface of the housing in any convenient configuration adapted to engage the pawl and arrest the rotation of the spool. The pawl is adapted to engage the ratchet to arrest the spool. Preferably the pawl includes a plurality of teeth adapted to selectively engage the ratchet. The pawl is mounted for rotation about an axis substantially parallel to and offset from the axis about which the spool rotates. The pawl may be mounted on a spigot or other axle. The pawl may thus be thrown out by its own inertia as the spool rotates. The pawl is biased to a disengaged position where the pawl is disengaged from the ratchet. The pawl may be biased by a spring or other mechanism to a disengaged position. The pawl may alternatively have an integral bias such as a member which is under tension or compression when the pawl is mounted on the inertia lock. When the inertia of the pawl is sufficient to overcome the bias the pawl is thrown outwards from the axis of the spool and into engagement with the ratchet. Preferably the pawl is oriented such that its net weight is not disposed radially from the axis of the spool and not also disposed radially from the axis of rotation of the pawl. In a preferred configuration, the pawl is aligned along a chord of the cross section of the spool and includes a weighted portion which is not disposed radially from the axis of the spool and not also disposed radially from the axis of rotation of the pawl. The inertia lock of the second aspect of the present invention may be used in applications other than the tethering apparatus of the first aspect of the present invention. The inertia lock may, for example in vehicle safety belt application. Other applications will also be apparent to those skilled in the art. The inertia lock may be attached to and abut the spool or may be disposed on a shaft or spindle about which the spool rotates. Where the inertia lock is attached to and abuts the spool the pawl may be eccentrically mounted on the spool and adapted to selectively engage a circular rack (or ratchet) formed on the inner surface of the housing. The tethering apparatus of the present invention may be provided with multiple line members each having a fixed end which is secured to the attachment means and a free end which is secured to suitable anchoring means. In order that this invention may be more easily understood and put into practical effect, reference will now be made to the accompanying drawings which illustrate a preferred embodiment of the invention wherein the tethering apparatus is applied to tethering a rock fisherman to the rocks. It will be appreciated that the application of the tethering apparatus to other uses will be apparent to those skilled in the art. The inertia lock shown in the drawings illustrates a preferred embodiment of the second aspect of the present invention, wherein: FIG. 1 is a schematic view showing tethering apparatus constructed in accordance with the present invention being used to tether a rock fisherman to a rock formation; FIG. 2 is a side view of a spool used in the construction of storage means for the tethering apparatus; FIG. 3 is a plan view of the spool illustrated in figure 2; FIG. 4 is a plan view of a housing used in the construction of storage means for the tethering apparatus; FIG. 5 is an end view of the housing illustrated in figure 4; FIG. 6 is a side view of the housing illustrated in figure 4; FIG. 7 is a side cross-sectional view of a spindle used in the construction of storage means for the tethering apparatus; FIG. 8 is a plan view of the spindle illustrated in figure 7; FIG. 9 is a plan view of the spring housing used in the construction of storage means for the tethering apparatus; FIG. 10 is a side view of the spring housing illustrated in figure 9; FIG. 1 1 is a cross-sectional plan view showing the pawl member used in the construction of storage means for the tethering apparatus; FIG. 12 is a plan view of a cover used in the construction of storage means for the tethering apparatus, and FIG. 13 is a side, view of the cover illustrated in figure 12. Figure 1 shows a rock fisherman 10 who is fishing from the edge of a rock formation and wherein the rocks on which he or she is standing may be covered with marine life including algae. To alleviate some of the dangers associated with falling from the rock formation into the sea 11 , the fisherman is tethered to a distant rock formation 13 located behind him using tethering apparatus 14. The tethering apparatus 14 includes a harness 15 releasably attachable to the fisherman's body, anchor 16 selectively securable to the rock formation 13 and a line member 17 connecting the anchor 16 to the harness 15. The harness 15 preferably includes a belt, not shown, which may be worn around the fisherman's waist. For safety reasons, the belt preferably includes a quick release buckle whereby the fisherman may quickly remove the belt, and thereby free himself from the tethering apparatus should he or she so desire. The belt also includes a spool having an inertia lock 18, mounted on a rear portion of the belt for storing or gathering selected portions of the line member 17 which are not required thereby enabling the fisherman to alter the extended or operative length of the line member 17 and in turn the extended distance separating them from the anchoring means 16. As shown in Figure 2, the spool having an inertia lock 18 includes a spool 19 consisting of two opposing circular guides 20 which are connected by an intermediate sleeve 21 . As shown in Figure 3, the spool 19 is mounted on a spindle 22 and is prevented from rotating relative to the spindle by the abutting engagement of the flat surface 23. As shown in Figure 7 the spindle 22 is mounted on a circular base 25 which includes two depending mountings 26 and 27. As shown in Figure 4, the spindle 22 and the associated spool 19 are retained within a generally cylindrically shaped housing 30 having an internal recess 31 which housing has in internal surface in the form of a toothed rack or ratchet 32. The spindle 22 is permitted to rotate about it's axis relative to the housing. As shown in Figure 9, the free end 28 of the spindle 22 is operatively connected to one end of a coiled spring, not shown, which is separately retained in a coiled or wound state within a cylindrically shaped housing 35 having a peripheral mounting flange 36 which enables the housing 35 to be mounted to the housing 30. The other end of the spring engages a slotted aperture 31 formed in a wall of the housing 35. The biasing forces exerted by the spring on the spindle 22, cause the spool 19 always exhibits a tendency to rotate in a direction which will assist with the winding up of the line member 17. As shown in Figure 11 , the tethering apparatus also includes an inertia lock 50 having a pawl 37 mounted on a spigot 26 and free to rotate about same. The pawl 37 includes a free end portion 38 which is equipped with a plurality of teeth 39 adapted to mesh with the toothed ratchet 32. The pawl 37 is connected to the mounting 27 by a spring 52 which exerts a biassing force on the pawl 37 such that it abuts the stop 53 when in disengaged condition. A shown in Figures 4, 5 and 6 the housing 30 also includes a pair of mounting flanges 40 which are used to mount the housing on the harness not shown. The flanges 40 being reinforced by supports 41. The housing 30 also includes an aperture 42 formed in a side wall 43 of the housing through which the line member contained on the spool 19 extends through during use. Furthermore, access to the recess, and in particular the spool 19, is selectively barred by the releasable attachment of a cover 44 to the upper peripheral edges of the side wall 43. The inertia applied to the spool as the line member is drawn therefrom, such as may occur due to a fall or when being dragged out by a receding body of water, may be sufficient for the pawl to overcome the biasing forces applied to same by the spring 52 and to operatively engage the ratchet 32. Thus, it will be appreciated that the tethering 10 apparatus may be used to secure a fisherman equipped with same to a fixed object, such as a rock formation, and wherein no additional line member shall be dispensed should the fisherman fall and/or become immersed in a body of receding water. As a consequence the risks of the fisherman being plunged into the sea and possibly drowning are reduced. It will be appreciated that the storage means may be used in other applications where the selective dispensing of a line member is desirable. It is to be appreciated that the above has been given only by way of illustrative example of the invention and that all such modifications and variations thereto as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of the invention as is herein defined in the appended claims.

Claims: Claims 1. A tethering apparatus including a harness, an anchor and a line member wherein said line member connects said harness to said anchor, further including a spool about which the line member is wound, said spool having an inertia lock for arresting the spool when the line member is unwound from the spool at a rate above a predetermined value. 2. A tethering apparatus according to claim 1 wherein the harness is in the form of a chair, a cradle, a pair of trousers, a pair of shorts, a belt, a jacket, life jacket, buoyancy vest or a shirt. 3. A tethering apparatus according to either claim 1 or claim 2 wherein the anchor is in the form of one or more hooks, karabiners, shackles, spikes which may be selectively driven into the ground or fasteners which expand so as to fill a void, such as a crack or crevice found in a rock formation. 4. A tethering apparatus according to any one of claims 1 to 3 wherein the line member is a rope or a cable. 5. A tethering apparatus according to any one of claims 1 to 4 wherein the spool is operatively connected to a return mechanism. 6. A tethering apparatus according to claim 5 wherein the return mechanism is a coiled spring, whereby the spool is urged to rotate in a direction which will gather the line member around the spool. 7. A tethering apparatus including a harness, an anchor and a line member wherein said line member connects said harness to said anchor, further including a spool about which the line member is wound, said spool having an inertia lock wherein the inertia lock includes a housing having an inner surface in the form of a ratchet, and a pawl mounted for rotation about an axis substantially parallel to and offset from the axis about which the spool rotates and wherein said pawl is biased to a disengaged condition where the pawl is disengaged from the ratchet and wherein said pawl engages the ratchet and arrests the spool when the line member is unwound from the spool at a rate above a predetermined value. 8. A tethering apparatus according to claim 7 wherein the harness is in the form of a chair, a cradle, a pair of trousers, a pair of shorts, a belt, a jacket, life jacket, buoyancy vest or a shirt. 9. A tethering apparatus according to either claim 7 or claim 8 wherein the anchor is in the form of one or more hooks, karabiners, shackles, spikes which may be selectively driven into the ground or fasteners which expand so as to fill a void, such as a crack or crevice found in a rock formation. 10 .A tethering apparatus according to any one of claims 7 to 9 wherein the line member is a rope or a cable. 11. A tethering apparatus according to any one of claims 7 to 11 wherein the spool is operatively connected to a return mechanism. 12. A tethering apparatus according to claim 1 1 wherein the return mechanism is a coiled spring, whereby the spool is urged to rotate in a direction which will gather the line member around the spool. 13. A tethering apparatus according to any one of claims 7 to 12 wherein the housing has an inner surface which is substantially cylindrical and includes a plurality of teeth to form the ratchet. 14. A tethering apparatus according to any one of claims 7 to 13 wherein the pawl includes a plurality of teeth adapted to selectively engage the ratchet. 15. A tethering apparatus according to any one of claims 7 to 14 wherein the pawl is mounted on a spigot. 16. A tethering apparatus according to any one of claims 7 to 15 wherein the pawl is biased by a spring to a disengaged position. 17. A tethering apparatus according to any one of claims 7 to 16 wherein the pawl is oriented such that its net weight is not disposed radially from the axis of the spool and not also disposed radially from the axis of rotation of the pawl. 18. A tethering apparatus according to any one of claims 7 to 17 wherein the pawl is aligned along a chord of the cross section of the spool and includes a weighted portion which is not disposed radially from the axis of the spool and not also disposed radially from the axis of rotation of the pawl. 19. An inertia lock for a spool of wound line member including a housing having an inner surface in the form of a ratchet, and a pawl mounted for rotation about an axis substantially parallel to and offset from the axis about which the spool rotates and wherein said pawl is biased to a disengaged condition where the pawl is disengaged from the ratchet and wherein said pawl engages the ratchet and arrests the spool when the line member is unwound from the spool at a rate above a predetermined value. 20. An inertia lock according to claim 19 wherein the harness is in the form of a chair, a cradle, a pair of trousers, a pair of shorts, a belt, a jacket, life jacket, buoyancy vest or a shirt. 21. An inertia lock according to either claim 19 or claim 20 wherein the anchor is in the form of one or more hooks, karabiners, shackles, spikes which may be selectively driven into the ground or fasteners which expand so as to fill a void, such as a crack or crevice found in a rock formation. 22 An inertia lock according to any one of claims 19 to 21 wherein the line member is a rope or a cable or a seat belt. 23. An inertia lock according to any one of claims 19 to 22 wherein the spool is operatively connected to a return mechanism. 24. An inertia lock according to claim 23 wherein the return mechanism is a coiled spring, whereby the spool is urged to rotate in a direction which will gather the line member around the spool. 25. An inertia lock according to any one of claims 19 to 24 wherein the housing has an inner surface which is substantially cylindrical and includes a plurality of teeth to form the ratchet. 26. An inertia lock according to any one of claims 19 to 25 wherein the pawl includes a plurality of teeth adapted to selectively engage the ratchet. 27. An inertia lock according to any one of claims 19 to 26 wherein the pawl is mounted on a spigot. 28. An inertia lock according to any one of claims 19 to 27 wherein the pawl is biased by a spring to a disengaged position. 29. An inertia lock according to any one of claims 19 to 28 wherein the pawl is oriented such that its net weight is not disposed radially from the axis of the spool and not also disposed radially from the axis of rotation of the pawl. 30. An inertia lock according to any one of claims 19 to 29 wherein the pawl is aligned along a chord of the cross section of the spool and includes a weighted portion which is not disposed radially from the axis of the spool and not also disposed radially from the axis of rotation of the pawl.

Inventors: BAKER CAMERON MACMILLAN, MCLAUGHLIN NEIL BERNARD, BAKER, CAMERON, MACMILLAN, MCLAUGHLIN, NEIL, BERNARD
Applicants: BAKER CAMERON MACMILLAN, MCLAUGHLIN NEIL BERNARD, BAKER, CAMERON, MACMILLAN, MCLAUGHLIN, NEIL, BERNARD
Application year: 2000
Main classification: A62B35
IPC codes: A01K97, A62B35, E04G21