GB2522553A - Improvements in and relating to zipwire trolleys - Google Patents

Abstract

A zipwire trolley 1 which comprises an inverted U-shaped frame 2 and at least one zipwire engageble roller 4, means such as an eye 5 below the roller for receiving a load to be carried via a karabiner or a sling, the frame also comprises a movable gate 8 for releasably locking the trolley to a wire. The gate being planar and including at least one lug or lug shaped locking formation 10 that co-operates with correspondingly shaped lug(s) or locking formation(s) 11 of the frame so that when the trolley is mounted on the zipwire and is under tensile load the gate is closed to provide mechanical support to the frame and gate. The trolley may include a safety mechanism in the form of a stepped latch and the roller may be mounted on bearings (17, fig.7) and associated axles (3, fig.7)

Description

This invention relates to zipwire trolleys, also known as zipwire PufiGys, fOr traversing wire cable stretched between anchor points, such as anthor points fixed to climbing towers within a wooded theme.park offering adventure actMties at height. There are typically several. zipwi.res to traverse at each such facility seØar&eci by ag rope walkways such that when one ipwire has been successfully traversed it ia neoessay to unhoo.k the zipwire trolley from the zipwire before then reaftachirig it to the next successive zipwire, the process JO continuing until the adventure course has been completed.

Zipwire trolleys typicMy include a pair of inline flanged rollers secured by n-spectjve xls to a frame of generally inverted "U'-shape., the frame having an opening below the rollers, to permit placement of the ?ollCrs onto a zipwire, the opening being closeable via a latch or gate biased to its closed position and.

openable to allow the zipwire to enter the ira me to thereby engage the rollers.

Whilst this general arrangement is simple ifl princlpie It will he understood that when a load is applied to the lower end ci the frame there is a tendanoy for it to.

splay apart or ctheiwise deform. Although this disadvantage can be obviated by ensuring that the size and thickness of the frame is sufficiently robust to reSt the tendency for it to deform under ten. ite. load, nevertheless it will be appreciated that this brings with it the dSdvantage that the size and/or weight Of the zipwire trolley ca be significant and. therefore not easily portable.

The loregoing problems are at least partially resolved in the teaching of 1JS681 0818 which discloses a double pulley device which again, uses a frame of generally inverted °U"-section havkiq an open end by whith the rollers can engage the zipwira but where instead of the load being applled to the lower end of the frame it is. applied above the zipwice itself by the simple expCdient of inserting a karabiner or snap-hook through an aperture in the frame so that loads borne by the karabiner are transmitted to the upper part of the frame tenthng to squeeze t together rather than splay a apart However attaching the icarahiner to the body ot the trolley in this manner may leave the karabiner vulnerab!e to high impact side loads when the. trolk.y collides with the end stop system of the zipwire.

to The present invention is derived froni the realisation that thera is a need for a. relatively lightweight and Si:mpie means of attaching a zipwire trojiey or pulley to a zpwire which is easily portable, safe and obviates the foregoing disadvanlages, According to the invention there Is provided a zipwire trolley comprising or includhng a frame of generally wwerted "U' shape and associated at least one zipwire en9agcabte roller, means on the frame below the at least one roller for receiving a toed to be carried via a karab.tner or sling, and a movoable gate. for releasabty locking the trolley to a zlpwire. tharacterised in that the gstS is generally planar and includes at least one generally planar iu ot uq-shaped locking formation cocperable with correspondingly shaped Jug(s) or locking formation(s) on or in the frame whereby when the ate is dosed the or each lug cooperates with the or each locking formation(s) to provde mechanical support for the frame and gate when the trolley is mounted en the zipwi.re and uPder tensile load, With this arrangement the at feast Ohs kig fits within: its respective correspondingly shaped torrnauon i.n the frame Or the gate in the manner of a jigsaw piece fitting to another jiósaw piece, thereby tending to reSist t.nsfle forces acting to separate them. This permfts the frame of the trolley to be rdabv&y lightweight since when the gate is closed the frame is no longer mechanically open-ended but instead constitutes a continuous structure or lOop capable of resisting any tendency for the frame to be splayed apart or otherwise deformed.

Conveniently, the or each iug, if on the gate, projects from the back-plate forming part of the gate.., the hack-plate being larger than the or each lug, by: which means the or each lug is prevented from extending through and beyond the correspondingly thaped fomation:(s) in the frame. This is a particulari.y convenient feature skies the or each lug Ond associatc: backplate. forming pai't of the gate can be generally smooth and planar, allowing for the trolley to be easily and simply fitted onto a zipwire and attached by the simple expedient of moving the gate from its closed' pOSition by pressing the gate against e.g. the bias øf a spring, The troUey ad'vantageousiy indudes as a safety mechanieth ógainst the acoident& openinq of the gate in the form of a stepped latch extendable enerally perpendicularly from the rear of the gate and being receivable within: a slot in the frame such that the gate can only be oØened after The latch has been moved to dear the. step, thereby allowing the gate to be fully opened far engagement or dis-'engagement of. the trolley with a zipwire. The stepped latch and associated slot therefore provide a second level of security for the. user of the trolley as the gate can cny be. opened ones the latch is flfted to the extent reuired to clear the step.

Preferably, the stepped latch is in the.: form of a cylindrical peg swivelably mounted at one end to the gate and having a neck portion towards the distal or "hea& end of the peg f smaller diameter to th:e peg, the neck porfion being co-operable within a corresoondingly sized slot in the frtne immediately above, a larger' slot throug.h whlch the head cn.rrob-ude. The extent of swivelling movement of the peg is limited by the presence of a step on or in the ga such that upon doWnward pressure of the head to the extent afforded by the presence of the step the peg thereafter acts as a h.ancfle by which, upon further downward pressure, th.e gate May be opened, In either or both kinds of latch mechanism the latch itself is preferably spring biased tà reieasably lock the gate in it dosed position, Conveniently, The or each roller is mounted on bearings and associated axles, the axles being partly hollow aic.ng their major axis for the purposes of permitting a.lubricantsuch as grsase. to be injected therewithin for lubricating the roller hearings. The open end of each axle' may include a oneway valve, such as a spring-hiaised ball cooperabie. w Ui a flang.e at the open end of the axle permitting lubricant to ony flow towards the centre of the axle and, via a bored hole, to the roller beanngs Conveniently, the flange is annular, havng a screw threaded outer suiface co*operable. with a screw-threaded bore M the free end of the axle whereby the flange and hence ball and associated spring Oan be releasably secured within the axie.

The invention will, now be descrd, .by way of example only, with eferen.ce to th9 accompanying drawiigs in which: Figure 1 is a perspective front view of a zipwirs trolley accorthn.g to the ihvention mounted on a zipwive.

5: Figure 2 is a. side view of the trolley of Figure 1 in its dosed position, Figure 3 is a perspective rear view of the trolley of Figure 1 in the closed position as &iown in Figure 2, Figure 4 is a side view of the trolley in flgure 1 in its open position Figure 5 is a perspective rear view of the trolley of Figure 4 in its open position, Figure 6 is a detalled perspective view of the opening mechanism of the trolley ci Figure 1 Figure 7 is a cross-semjon of the uØber part of the trolley through one of the rollers, Figure 8 is a side view of an alternative operating mechanism to that shown with. reference to Figures 1 to 6, Figure is a perspective view of the trolley with th rnechanithm. as shown in Figure 8, Figure 10 is a sectional side view of the trolley shown in Figure 8, and Figure 11 is a side view of the trolley of Figure 8 in which the gate is.

shown ft. its open poslijop, Referring firsUy to Eiure 1 zipwire trolley shown generally at I includes a trolley frame 2 of generally inveited "U'shape heving a frontplate 2a and a rear-plate 2b between which are sandwiched a pair of axles 3 and associated flanged rollers 4, one of which is shown more dearly in Figure 7.

At the lower end Of the rear-pat 2b is an aperture definihg an eye S for receiving a kara.biner.6 or other load-carrying means such: as a sling at strap.

Above the eye 5 are a pair of ribs 7 extending twin the rear-plate 2b for receiving aQorrespond.ing, !otted gate 8 pivota.lly mounted on the ribs 7 vi:a a pivot pin 9 as shcwn in FIgure 2, the gate a Sing biased to the dosed position shown in Fiçure 2 via a spring (tlot. shOwn), At the end of the gate 8 remote from the pivo t pin 9 are a pair of pert to circular ugs 10 received within a pair of correspordingly shaped locking formations Ii in the front-plate 2a so that they: inter-engage in the manner of a pair of nterIotking jigSw pieces..

As shown more dearly with reference to Figure 6 the Jugs 10 project from a back-plate 12 fOrming pj of the gate 8 such that the Jugs 10 are prevented from extending through the apertures 11 beyond the: limit imposed by the back-pirne 2 Hence, n the condrhon shown n Figure 2 the gate 8 s effecbvely structurally connected to and forms pad of the frame 2 such that tensile loads applied to the eye. 5 are transmitted directly to the rear-plate 2b and indirectly to the front plate 2a via the gate 8 and associated logs 10.. This arrangement is paflicularly convenient because lit allows the frame 2 to be made from relatively thin-walled front and rear-plates 2a, 2b without ecmpitmisihg the integdty of the frame when under load. In. addition, because the logs 10 do not extend bEyond the major plane of the gate a they do not. intertere wfth. or otherwise. snag: against the. zipwire Z as the trolley I is being mounted or dis-mounbd.

The presen of the back-plate 12 immediately behind the tugs 10 and the biasing of the gate S towards the apertures 11 in the froni-plate 2e provide a first safety mechanistt whereby the gate 8 is biased to its closed position as shown in Figure 2. However. in a nother aspect the. invention also indudes a 5. second safety featLire in th:e form of a stepped latch 1.3 extending perpenthcutady from a latch pn 14 and assocaten latch recennng recess (not shown) in the rear of the gate 8, the atch 13 being receiyble within a correspondingly shaped s'ot 15 (shown in Figures 3 and 5) by which the step 16 can be Rfted to the position shown in Figures 4 and 5 in which the gate 8 become fully opened. This stepped tching mechanism therefore provides an additiona safety feature such that acddenthl pressure on the dosed gate 8 will no.1 cawe it to be opened and thereby prescnt a safely hazard, it being necessar1 to lift the latch 13 befOre the gate 8 can be moved to its Open po&tion in a further refinement to the invention and as shown in. Figure 7 each axe 3 is partially hollow at one end to. allow for lubrication of bearings 17 for each roller 4. The open end IS of the axle 3 j diosed by a threaded flange 19 iich acts as a valve seat against a ball bearing 20 biased by spring 21 against the flange 19 A bored hole 22 of smaller diameter than the spring 21 leads to the bearings 17 auth that a lubricant Such as. grease can be pumped under pressure beyond the ball hearing 20 as required, whereafter the hail bearing 20 serves to seal access to the cOnduit22 by contamnants such as water including saltWater which could otherwise lead to corrosion or the bearings 17. This arrangement also means that the rollers 4 and attendant bearings 17 do not have to be removed from the frame 2 when the zpwire trolley I s bemg sennced Turning now to the embodiment of the invention shown with reference to Figures 8 to 11, the latch mechanism in this instance comprises a cylindrical peg 23 swivelably mounted at one end to the gate Ba via, a pivot pin 14a and having.

at its distal end a head portiøn 24 of corresponding diameter to the peg portion 23, and there between a neck portion 25 of smaller diameter so that it can fit withn a coaespondinglysJzed slot 26. immediately above a larger-diameter slot 27 in. the rear pate b as shown ii figure 1Z In the position shown the head 24 of the. pin 23 id at an intermediate position in which the neck portion 25 ban be forced into the slot 26 by the action of a biasing spring (not shown) or it can.

10. instead, be forced downwards to the position shown in Frgure 11 by thur;b-pressure., in which poition the gate Ba is forced to. the open position shown, thereby ailowing the halley to be mounted or di$mounted ontO or from a zipwira.

The gate B.c includes a stepped recess 26 imiting the swivelling movement of the peg 23 to the extent afforded by the tower end of the slot 27,. corresponding to the maximum extent of swweJabe travel of the gate Ba from the fuHy closed poston shown in Figuie 8 to the tuily opened pos!tion shown in Figure 11 Thus, with. this embodiment of the invention the gate Ba ban be manually' opøned.

from the rear by downward pressure on the head. 24.

The in its various spfl therefore provides a relatively hghtweight zpwire twlley whch can be easily attached and detached from a zipwire. without the ri,k of accidental entanglement as the zipWre passes the gate 8, which itsff can only open after operation of the latch.43 Mtending out of the elot 15 in the rear plate 2b., although it will be understood that the provision of the latch mechanism itself is an optional feature of the invention. Similarly7 the ftivention is not limited to the provision of the lubrication mechanism shown with. reference to Figure. 7 and although two lugs S and associated $pertures 1.0 are shown it will be understood that only one or more than two lugs may be provided as requIred. Sir:ilariy, the lus may be of inverted form extending: from S the front-plate 2a with correspondingly shaped apertures: in the gate B to thereby provide a mechancaj connection between the front and rear-plates.2a, 2b when under tensile load. The lags and wrre pending locking fórrnatine may be of any suitable shape, although part-circular is preferred for simplicity of manufacture and also because lags of that shape are less likely to snag the *lo Zipwite.