CN112930221A

CN112930221A - Sliding vehicle

Info

Publication number: CN112930221A
Application number: CN201980052305.8A
Authority: CN
Inventors: 大卫·尼古拉斯·埃文斯
Original assignee: Castelli Engineering Co ltd
Current assignee: Castelli Engineering Co ltd
Priority date: 2018-06-08
Filing date: 2019-06-07
Publication date: 2021-06-08
Also published as: EP3817833B1; WO2019234441A1; EP3817833A1; EP3817833C0

Abstract

A trolley (100) for a track (10) is described. The sled (100) comprises: a frame (110); a set (S) of wheels (120) rotatably coupled to the frame (110), comprising a first wheel (120A) and a second wheel (120B); an attachment member (130) coupled to the frame (110) for suspending a load (W) in use. The first wheel (120A) is rotatable about a first axis (a1) in a first plane (P1), and the second wheel (120B) is rotatable about a second axis (a2) in a second plane (P2). The first plane (P1) and the second plane (P2) define a line (L). The sled (100) may be arranged in a first configuration with the attachment member (130) arranged at a first angular displacement (D1) about the line (L). The sled (100) may be arranged in a second configuration with the attachment member (130) arranged at a second angular displacement (D2) about the line (L). The first angular displacement (D1) and the second angular displacement (D2) are different. A track assembly (1) comprising a trolley (100) and a track (10) is also described.

Description

Sliding vehicle

Technical Field

The present invention relates to a trolley for a track and a track assembly comprising a track and such a trolley.

Background

Typically, a strop (also known as a fly line, sling, aerial runway or aerial rope slide) comprises an inclined cable fixed only at its upper and lower ends and a trolley (trolley) (also known as a trolley (bogey)) comprising a freely rolling pulley. A user (i.e. a load) suspended from the trolley may accelerate by gravity from the upper end to the lower end of the tilting cable. In use, the pulley rolls along the uppermost portion of the tilting cable. The inclination of the tilting cable is typically in the range 1/20 to 1/30. Typically, the tilting cables sag and proper tensioning of the tilting cables is required to control the acceleration of the user. Since the tilting cables are fixed only at their upper and lower ends, the tilting cables are constrained to a straight path without lateral offset, such as curves or bends.

To provide a non-linear path including lateral offsets, such as curves or bends, the cable may be replaced by a track (typically a monorail). For example, the non-linear path enables the track to bend around obstacles and/or increases user enjoyment. For example, the uppermost portion of the track may be fixed to a frame or suspended from ceiling joists or trees, leaving the area below the track unobstructed for the passage of trolleys and users. A typical rail comprises a tube for fixing or hanging, which tube has an axial (also called longitudinal) flange standing upright on the tube. The pulleys are replaced by one or more freely rolling wheels that roll along the track on one or more upper lateral portions of the track, avoiding the fixed uppermost portion. For example, the wheel may roll on either side of the axial flange. While the track may include one or more of a descending section, an ascending section, and/or a horizontal section, the track is generally inclined with an average inclination generally in the range of 1/10 to 1/60.

However, a trolley for a track may sometimes unexpectedly become bound and thus braked on the track. This may result in injury to the user, such as a whiplash injury due to sudden deceleration. In addition, the user may get stuck on the track due to the stopped trolley, requiring rescue. Furthermore, the following carriage may collide with the stopped carriage, which may also lead to injuries. To reduce the increase in track inclination due to binding induced braking, the speed of the trolley is increased, contrary to the need for increased safety.

Accordingly, there is a need for improved carriers for rails, for example to improve user safety and/or carrier reliability.

Disclosure of Invention

Among others, it is an object of the invention to provide a trolley, a track assembly comprising a track and a trolley, and a kit of parts for a track assembly comprising a track and a trolley, which at least partly obviate or mitigate at least some of the disadvantages of the prior art, whether identified herein or elsewhere. In this way, the safety of the user and/or the reliability of the carriage can be increased.

According to a first aspect, there is provided a trolley for a track, the trolley comprising:

a frame;

a wheel set including a first wheel and a second wheel, the wheel set rotatably coupled to the frame; and

an attachment member coupled to the frame for attaching, preferably suspending, a load in use;

wherein the first wheel is rotatable about a first axis in a first plane and the second wheel is rotatable about a second axis in a second plane;

wherein the first plane and the second plane define a line;

wherein the sled is arrangeable at:

a first configuration in which the attachment member is arranged at a first angular displacement about the line; and

a second configuration wherein the attachment member is disposed about the wire at a second angular displacement, wherein the first and second angular displacements are different.

According to a second aspect, there is provided a track assembly comprising a track and a trolley according to the first aspect.

According to a third aspect, there is provided a kit of parts for a track assembly comprising a track and a trolley according to the first aspect.

Detailed description of the invention

According to the present invention there is provided a tackle as claimed in the appended claims. A track assembly and a kit of parts for a track assembly are also provided. Further features of the invention will be apparent from the dependent claims and the following description.

a frame;

wherein the first plane and the second plane define a line;

wherein the sled is arrangeable at:

It will be appreciated that in use, due to gravity, the load causes (i.e. induces) a downward vertical force which may be applied at least in part via the trolley to the track. The load may cause (i.e., induce) other forces that may be exerted on the trolley and/or on the track via the trolley, for example due to pitch, yaw, and/or roll of the load and/or due to centripetal forces on the load (as described below). It should be understood that while the track may include one or more of a descending portion, an ascending portion, and/or a horizontal portion, the track is generally inclined with an average inclination generally in the range of 1/10 to 1/60. For example, the track may comprise an initial length having an average inclination of about 1/13 (to initially accelerate the trolley), followed by an intermediate length having an average inclination of about 1/25 (corresponding substantially to a constant speed of the trolley) and a final length having an average inclination of about 1/50 (to decelerate the trolley).

The inventors have determined that conventional carriers sometimes become accidentally bound and thus braked on the track due to increased lateral forces on the track (i.e. lateral forces transverse to the line). These increased lateral forces on the track may be due to centripetal forces as the trolley travels around a curved portion of the track and/or due to swinging of the load (e.g. the user swings from side to side). Accidental binding and thus braking is usually caused by the user swinging from side to side, which may be neither anticipated nor prevented.

Since the attachment member is movable between the first configuration and the second configuration, lateral forces on the rail may be reduced compared to, for example, a fixed attachment member. In this way the possibility of the trolley becoming bound to the track and thus braked is reduced. In this way, the likelihood of injury and/or entrapment of the user may be reduced. In this way, the safety of the user and/or the reliability of the carriage can be increased.

Furthermore, since lateral forces on the rail may be reduced, for example, as compared to a fixed attachment member, the number of wheels comprised in the wheel set and/or the size of the wheels comprised in the wheel set may be reduced, as described in more detail below. Additionally and/or alternatively, the strength of the frame may be reduced. In this way, the weight and/or cost of the tackle may be reduced. For example, the mass of the sled may be reduced from about 4.8kg to about 3.7kg (i.e., about 22%) due to the reduction in lateral forces. Instead, an increased load may be attached to the trolley.

Load(s)

Typically, the load comprises and/or is a user, the mass of which is in the range of 30kg to 120kg, and thus the weight is in the range of 294N to 1177N. Further, the centripetal force due to the turning may increase to 1.5g in the horizontal direction (i.e., up to 441N to 1766N). Furthermore, the increased vertical load due to the downward swing (e.g., the user swinging from a tilted to a vertical position) may increase vertically to 0.6g (i.e., as much as 176N to 706N) without a horizontal component. For example, a user may be attached to the attachment member via a harness (also referred to as a hanging harness). For example, the harness may include a back D-ring for attachment to the attachment member via a sling or tether. In this way, in use, a user may hang in a hang glider type (also known as superman) position (i.e. prone or face down). The sled may include a handle for gripping the handle when the user is in such a prone or face-down position.

Sliding vehicle

The trolley (also referred to as trolley) is adapted for use with a track (also referred to as a skid) and is arranged to roll thereon. Typically, the trolley is held on the track, for example by a set of wheels, so that the trolley cannot be removed from the track (i.e. fall out) in use.

The sled includes a frame to which the set of wheels is rotatably coupled and to which the attachment member is coupled. That is, the frame transfers the force due to the load to at least one of the plurality of wheels in the wheel set, such as the first wheel and/or the second wheel. In one example, the frame comprises an open structure (also referred to as a frame or cage) provided, for example, by one or more struts and/or one or more ties. In one example, the frame includes an enclosed structure and/or a single shell structure. In one example, the frame includes a channel for the track to pass through.

Wheel set

The trolley includes a wheel set including a first wheel and a second wheel, the wheel set rotatably coupled to the frame. The force due at least in part to the load is transmitted via the frame to at least one of the plurality of wheels in the wheel set, such as the first wheel and/or the second wheel.

In one example, the first and second wheels are arranged to roll on one or more upper and/or lateral portions of the track, thereby at least partially transferring weight due to the load to the track and/or transferring forces due to movement (e.g. pitch and/or yaw) of the load to the track. In one example, the first wheel and the second wheel are disposed at opposite ends of the frame. In one example, the first wheel and the second wheel are disposed at the same end of the frame. In one example, the first wheel and the second wheel are arranged on opposite sides of a channel in the frame, whereby the first wheel and the second wheel are arranged on opposite sides of the track in use. In one example, the set of wheels comprises a third wheel, as described in relation to the first wheel and/or the second wheel, the first wheel and the second wheel being arranged at opposite ends of the frame and the third wheel being arranged on opposite sides of a channel in the frame, whereby in use the first wheel (and the second wheel) and the third wheel are arranged on opposite sides of the track. In one example, the set of wheels includes a third wheel and a fourth wheel, as described with respect to the first wheel and the second wheel, respectively. In one example, first and second wheels are disposed at opposite ends of the frame, third and fourth wheels are disposed at opposite ends of the frame, the first and third wheels are disposed on opposite sides of a channel in the frame, and the second and fourth wheels are disposed on opposite sides of the channel in the frame.

In one example, the set of wheels is arranged to hold the trolley on the track so that the trolley is not removed (i.e. disengaged) from the track in use. In other words, the carriers are bound to the track, thereby improving safety.

In one example, the set of wheels is arranged to at least partially resist forces in 1, 2 or 3 mutually orthogonal directions, for example due to the weight of the load and/or the trolley pitch, roll and/or yaw. In a preferred example, the set of wheels is arranged to at least partially resist forces in 2 mutually orthogonal directions, for example due to the weight of the load and/or the trolley pitch, roll and/or yaw, whilst allowing movement of the trolley in a third mutually orthogonal direction, for example down and/or up the track.

In one example, the set of wheels includes 3 or more wheels.

Wheel set

In one example, the wheel set includes a first wheel subset, the first wheel set includes a first wheel, a second wheel, and optionally a third wheel and/or a fourth wheel. In one example, the first wheel set includes more than four wheels. In one example, the first wheel set is arranged to roll on one or more upper and/or lateral portions of the track and thereby at least partially transfer weight due to the load to the track and/or force due to movement (e.g. pitch and/or yaw) of the load to the track. In this way, pitch and/or yaw of the trolley about the track can be resisted. In one example, the wheel set includes a second wheel sub-set including a fifth wheel, and optionally, a sixth wheel, a seventh wheel, and/or an eighth wheel. In one example, the second wheel set includes more than four wheels. In one example, the second wheel set is arranged to roll on one or more lower and/or lateral portions of the track, thereby at least partially transferring forces generated by movement (e.g., pitch and/or yaw) of the load to the track. In this way, pitch and/or yaw of the trolley about the track can be resisted. In one example, the set of wheels includes a third subset of wheels including a ninth wheel and, optionally, a tenth wheel. In one example, the third subset of wheels includes more than two wheels. In one example, the third wheel subset is arranged to roll on one or more lateral portions of the track, thereby at least partially transferring forces generated as a result of movement (e.g., rolling) of the load to the track. In this way, rolling of the trolley around the track can be resisted. That is, the wheels of the second and/or third wheel sub-groups improve stability in use and may be referred to as stability wheels. In one example, the wheels included in the second and/or third wheel sub-groups are relatively smaller and/or lighter than the wheels included in the first wheel group. In particular, since lateral forces on the track may be reduced compared to a fixed attachment member, the size and/or weight of the wheels comprised in the second and/or third wheel sub-group may be reduced, for example.

In one example, in use, one or more or all of the wheels of the wheel sub-group comprising the first wheel and the second wheel are typically in contact with the track. In one example, in use, one or more or all of the wheels of the subset of wheels and/or the subset of wheels are not normally in contact with the track, spaced from the track by a gap in the range 1mm to 10mm, preferably 3mm to 7mm, but may contact the track during yawing, pitching and/or rolling of the carrier.

In one example, the third wheel is rotatable in a first plane about a third axis parallel to the first axis and the fourth wheel is rotatable in a second plane about a fourth axis parallel to the second axis, wherein the first and second planes define the line. In one example, the wheels included in the first wheel sub-group define the line. In one example, the wheels included in the first and second wheel sub-groups define the line.

Wheel alignment

The first wheel is rotatable about a first axis in a first plane and the second wheel is rotatable about a second axis in a second plane, wherein the first plane and the second plane define the line.

In one example, the first axis and the second axis are coaxial, whereby the first plane and the second plane are coplanar or parallel. If the first and second planes are coplanar, the line is defined in the first and second planes. If the first and second planes are parallel, the line is defined between the first and second planes, e.g., equidistant from the first and second planes. In one example, the first axis and the second axis are mutually inclined, whereby the first plane and the second plane are mutually inclined. If the first and second planes are inclined to each other, the line is defined by the intersection of the first and second planes. In one example, the line is an intersection of the first plane and the second plane. In a preferred example, the line is the intersection of a first plane and a second plane, and the track comprises a cylindrical running surface defining a cylinder axis, wherein the line is substantially coincident with the cylinder axis in use. In one example, in use, the line substantially coincides with the cylindrical axis when the line is within 20%, preferably within 15%, more preferably within 10%, most preferably within 5% of the cylindrical axis, expressed as a percentage of the radius of the cylindrical running surface.

In one example, the first axis and/or the second axis is tangent to a radius perpendicular to the line.

Wheel of vehicle

In one example, the first wheel comprises a tire formed from a polymer composition, such as a thermoplastic (e.g., polyurethane or nylon), having one or more bearings, such as ball bearings (e.g., deep groove ball bearings). Polyurethane is preferred. In one example, the bearings are sealed (i.e., have seals also known as dust caps or seal caps) to reduce maintenance requirements and/or improve safety. ZZ-, 2 RS-and/or 2 RU-type seals are preferred. In one example, the outer diameter of the first wheel (e.g. the tyre of the first wheel) is in the range 40mm to 80mm, preferably in the range 50mm to 70 mm. Smaller wheels tend to provide greater stability and faster acceleration, while larger wheels are smoother on rough surfaces and are suitable for higher speeds. In one example, the hardness of the first wheel (e.g., the tire of the first wheel) is in the range of 70a to 110a (determined using a durometer). Softer wheels (e.g., 70a) have better grip, while harder wheels (e.g., 100a) are faster. In one example, the first wheel is a flat wheel (i.e., has a cylindrical rolling surface) and thus has a relatively large contact patch (i.e., surface area). In one example, the first wheel has a width in the range of 5mm to 40mm, preferably in the range of 10mm to 30 mm.

In a preferred embodiment, the first wheel comprises a polyurethane roller, for example with an outer diameter of 62mm, in combination with a deep groove ball bearing, for example SKF 6301ZZ deep groove ball bearing with a 12mm bore and a 12mm length.

In one example, the first wheel is mounted on an axle, wherein the axle is fastened to the frame. In one example, the shaft includes and/or is a mechanical fastener, such as a threaded fastener such as a bolt, fastened to the frame, for example using a nut or threaded into a threaded hole in the frame. In one example, the first wheel comprises an adjustable first wheel. In this way, the clearance of the first wheel from the track may be adjusted, for example to account for wear of the first wheel and/or the track, and/or to apply a preload to the first wheel, for example to control pitch, roll or yaw of the carrier. In one example, the axle comprises an eccentric axle, whereby the first wheel comprises an adjustable first wheel.

In one example, the first wheel is a driven wheel (i.e., not driven). In one example, the first wheel is a drive wheel (i.e., driven). In one example, the trolley comprises a drive, such as an electric motor and optionally a power supply and/or power controller, arranged to drive the first wheel.

The second wheel may be as described with respect to the first wheel. Each wheel of the wheel sub-set may be as described with respect to the first wheel. In one example, the wheels comprised in the second and/or third wheel sub-groups are relatively smaller and/or lighter than the wheels comprised in the first wheel sub-group. In one example, the outer diameter of the wheels comprised in the second and/or third wheel sub-group is in the range of 20 to 60mm, preferably in the range of 30 to 50 mm. In one example, the width of the wheels comprised in the second and/or third wheel sub-group is in the range of 5 to 30mm, preferably in the range of 10 to 20 mm.

Attachment member

The trolley comprises an attachment member coupled to the frame for attaching, preferably suspending, a load in use. In this way, the load may be attached (preferably suspended) to the frame.

In one example, the attachment member is releasably coupled to the frame. In one example, releasing the attachment member from the frame requires the use of a tool. In this way, unintentional or intentional release of the attachment member during use may be avoided, thereby improving safety. In one example, the attachment member includes a fastener, such as a pin fastener, a cotter pin (also known as a cotter pin, cotter key, or cotter pin), a locking ring, a hook latch, or a clamp, to limit release of the attachment member from the frame. In this way, unintentional or intentional release of the attachment member during use may be avoided, thereby improving safety. In one example, the attachment means comprises a shackle (also known as a shackle), typically a U-shaped piece of metal secured with a U-shaped pin or bolt through its opening, or a hinged metal ring secured with a quick release locking pin mechanism. In one example, the shackle is a bow shackle, a D shackle, a headboard shackle, a pin shackle, a snap shackle, a threaded shackle, or a twist shackle. The pin shackle, which is closed by the anchor bolt and the cotter pin and which comprises a fixing nut in addition to the cotter pin, is preferred, since unintentional or intentional release of the attachment member can be avoided in use. Threaded shackles with hook openings are also suitable. Quick release shackles (e.g. snap shackles or climbers) can be easily released in use, even with one hand, and are generally not preferred. In general, quick release attachment members are not preferred. In one example, the attachment member does not include and/or is not a quick-release attachment member, such as a quick-release shackle.

First and second configurations

The trolley may be arranged:

the first configuration wherein the attachment member is disposed about the line at the first angular displacement; and

the second configuration, wherein the attachment member is disposed about the wire at the second angular displacement, wherein the first and second angular displacements are different.

As described above, since the attachment member is movable between the first configuration and the second configuration, lateral forces on the rail may be reduced compared to, for example, a fixed attachment member. In this way the possibility of the trolley becoming bound to the track and thus braked is reduced. In this way, the likelihood of injury and/or entrapment of the user may be reduced. In this way, the safety of the user and/or the reliability of the carriage can be increased.

In one example, the height or elevation of the attachment member at the second angular displacement is greater than the height or elevation at the first angular displacement. That is, the second gravitational potential energy of the load when the trolley is disposed in the second configuration is greater than the first gravitational potential energy of the load when the trolley is disposed in the first configuration. That is, work must be done to move the attachment member from the first configuration to the second configuration. In this way, the movement of the load and thus the attachment member transverse to the line may be controlled, e.g. slowed down.

In one example, the trolley is arranged to move from the first configuration to the second configuration as a result of a force transverse to the line (i.e. a lateral force), the force being caused at least in part by movement of the load transverse to the line. For example, as the trolley travels around a curved portion of the track, the load may move transverse to the line due to centripetal forces thereon. For example, the load may move transverse to the line due to swinging of the load, e.g. by the user swinging from side to side (i.e. rolling of the trolley).

In one example, the attachment member is arranged to move in an arc (e.g., increasing height or elevation) about the line from a first angular displacement to a second angular displacement. In this way, the movement of the attachment member may be smooth, enhancing the user's experience and/or safety, while work must be done to move the attachment member from the first configuration to the second configuration, as described above. In a preferred example, the track comprises a cylindrical running surface defining a cylindrical axis, wherein, in use, the line is substantially coincident with the cylindrical axis, the attachment member is arranged to move in an arc about the line from a first angular displacement to a second angular displacement, and the arc is concentric with the cylindrical running surface.

In one example, the sled includes a mechanical link coupled to the frame and the attachment member is coupled to the mechanical link. In one example, the mechanical linkage comprises a planar four-bar linkage, such as a planar quadrilateral linkage. In this way, the attachment member may be arranged to move in an arc (e.g., increasing height or elevation) about the line from the first angular displacement to the second angular displacement.

In one example, the attachment member is arranged to rotate about the line, whereby, in the first configuration, the attachment member is arranged to rotate about the line at a first angle; thereby, in the second configuration, the attachment member is arranged to be in a second angular rotation around the line, wherein the first angular rotation and the second angular rotation are different.

Guide piece

In one example, the trolley comprises a guide coupled to the frame, the guide arranged to guide the attachment member between the first configuration and the second configuration. In this manner, movement of the attachment member may be guided (e.g., controlled, limited, and/or constrained). In one example, the guide includes an arcuate portion. In this way, the attachment member may be arranged to move in an arc (e.g., increasing height or elevation) about the line from the first angular displacement to the second angular displacement. In one embodiment, the arc subtends an angle in the range of 15 ℃ to 270 ℃, preferably in the range of 45 ℃ to 180 ℃, more preferably in the range of 60 ℃ to 120 ℃, for example about 90 ℃ or about 100 ℃. In one example, the guide has a circular cross-section, whereby the guide comprises and/or is a round rod or tube. In one example, the guide has a diameter in the range of 5mm to 50mm, preferably in the range of 10mm to 20 mm. For example, a round bar can be easily formed to include an arc-shaped portion. In one example, the guide is formed from a material having a hardness (rockwell B) in a range of 50HRB to 100HRB (1/16 ″, 100kg) a yield strength in a range of 150MPa to 400MPa, an elongation at break in a range of 10% to 80%, an elastic modulus in a range of 150 to 400GPa, and/or a charpy impact (EN10045-1) in a range of 100J to 400J. Corrosion resistance is preferred. SAE 304 and 316 type (preferably) stainless steels are suitable.

In one example, the attachment member comprises a shackle, and the shackle is arranged to slide on the guide. The guide may be lubricated, for example, with grease, molybdenum disulphide and/or Polytetrafluoroethylene (PTFE), and/or may comprise a plain bearing, for example a phosphor bronze, cast iron or Polytetrafluoroethylene (PTFE) plain bearing.

Roller wheel

In one example, the attachment member comprises a roller arranged to roll on the guide. In this way, the trolley is arranged to move, for example in an arc, from the first configuration to the second configuration by the attachment members rolling on the guides. In this way, resistance to movement of the attachment member due to friction between the attachment member and the guide can be reduced. In this way, wear of the guide and/or the attachment member may be reduced compared to sliding of the attachment member, thereby reducing maintenance requirements and/or improving safety. In one example, the attachment member includes one or more bearings, such as ball bearings (e.g., deep groove ball bearings), and the roller is mounted thereon. In this way, the resistance to movement of the attachment member due to friction between the attachment member and the guide can be further reduced. In one example, the bearings are sealed (i.e., have seals also known as shields or seals), thereby reducing maintenance requirements and/or increasing safety. ZZ-, 2 RS-and/or 2 RU-type seals are preferred. In one example, the attachment member includes one or more shims, such as washers, disposed alongside the bearing, for example, to space the bearing from the two legs of the shackle.

In one example, the roller is a grooved roller, for example having a circumferential groove (e.g., a circumferential arc groove). In one example, the maximum outer diameter of the roller is in the range of 20mm to 50mm, preferably in the range of 30mm to 40 mm. In one example, the roller is a grooved roller having a circumferential arc groove, and the guide has a circular cross-section. In one example, the radius of the groove corresponds to the radius of the guide. In one example, the radius of the groove is at least the radius of the guide. In one example, the radius of the groove is larger than the radius of the guide, for example in the range of 1% to 20%, preferably in the range of 3% to 10%. In this way, the attachment member may rotate about the normal to the line, while maintaining a sufficiently large contact area between the roller and the guide, thereby reducing contact stresses thereon.

In one preferred example, the attachment member includes: a pin shackle closed with an anchor bolt and a cotter pin and including a fixing nut in addition to the cotter pin; and a grooved roller having a circumferential arc groove, wherein the grooved roller includes two ball bearings, the grooved roller being mounted on an anchor bolt between two shackle legs, spaced apart from the shackle legs by two spacers.

In one example, the attachment member may be rotatable about a normal to the line, such as provided by the radius of the groove being greater than the radius of the guide or rotating member (e.g., rotating shackle). Other means of providing such rotation are known. In this way, twisting of the load relative to the trolley can be accommodated.

In one example, the roller is formed from a material having a hardness (rockwell B) in the range of 50 to 100HRB (1/16 "balls, 100kg), a yield strength in the range of 150 to 600MPa, an elongation at break in the range of 10 to 80%, a modulus of elasticity in the range of 150 to 600GPa, a charpy impact (EN10045-1) in the range of 100 to 500J, and/or a fatigue limit in the range of 100 to 500MPa (preferably 200 to 400 MPa). In particular, the present inventors have determined that repeated rolling of the roller on the guide and/or relatively high contact stresses due to the relatively small contact area between the roller and the guide may cause the roller and/or the guide to fail, such as crack. Without wishing to be bound by any theory, it is understood that repeated rolling, combined with relatively high contact stresses, results in fatigue crack initiation and/or propagation. Corrosion resistance is preferred. SAE 304 and 316 (preferably) stainless steels are suitable. For example, rollers may be coated or polished to improve fatigue resistance.

Multiple attachment members and/or guides

In one example, the trolley comprises a plurality of attachment members and/or guides, for example a corresponding plurality of guides, each attachment member and guide being as described above. In one example, the sled includes two attachment members and two guides.

Track assembly

As noted above, it should be understood that the track is generally inclined, although the track may include one or more of a descending portion, an ascending portion, and a horizontal portion. In one example, the track includes a descending portion, an ascending portion, and/or a horizontal portion.

In one example, the track includes a non-linear, e.g., curved, portion. In this way, for example, the non-linear portion enables the track to bend around obstacles, and/or increases user enjoyment, as described above. It will be appreciated that the non-linear portion is generally lateral, although the track may be curved laterally and may also be curved upwardly or downwardly.

In one example, the track comprises two or more tracks, for example two parallel tracks. In one example, the track is a monorail (i.e., a single track). Monorail is preferred to reduce cost and/or weight, for example, can be easily fixed to a rack or hung from a ceiling joist or tree, and/or can be formed into relatively complex shapes, including multiple non-linear and linear portions that can also rise, fall and/or level.

In one example, the track comprises a planar (i.e. flat) running surface, for example provided by a square or rectangular bar or hollow section and/or an equiangular or non-equiangular section. In one example, the track includes a non-planar surface, such as a convex or concave riding surface. In one example, the track comprises a cylindrical (i.e. convex) running surface defining a cylindrical axis, wherein in use the line substantially coincides with the cylindrical axis, for example formed by a tube (i.e. a profile) having a circular cross-section or a portion thereof (e.g. a U-shaped channel). Hollow profiles are preferred to reduce the weight of the rail. In one embodiment, the tube has an outer diameter in the range of 40mm to 100mm, preferably in the range of 50mm to 75mm, and/or a wall thickness in the range of 1mm to 6mm, preferably in the range of 2mm to 5mm, for example 3mm or 4 mm.

In one example, the track includes a longitudinal flange (i.e., a fixture). In this way, for example, the track may be secured to a frame or hung on ceiling joists or trees such that the area below the track remains unobstructed for the passage of trolleys and users. In one example, the longitudinal flange extends continuously along the length of the track. In one example, the longitudinal flange includes one or more perforations or brackets for securing. Other securing means are known. In one example, the flange is welded to the profile, for example continuously or intermittently.

In one example, the track is formed by a track according to EN 10025: section 2: grades 2004S 185, S235, S275, S355 steel or equivalent standard steel. In one example, the rails are coated (e.g., painted and/or galvanized) to improve corrosion resistance.

In one example, the track is provided in length sections, which are coupled end-to-end, for example, on site.

In a preferred embodiment, the track comprises a cylindrical running surface defining a cylindrical axis, wherein, in use, the line substantially coincides with the cylindrical axis provided, for example, by a tube having a circular cross-section, and the track comprises a longitudinal flange perpendicular to (i.e. upstanding on) the tube, the longitudinal flange extending continuously along the tube.

The track may be as described in relation to the second aspect.

Throughout this specification the term "comprising" is intended to include a stated component or components, unit or units, module or modules, feature or integer or integers but not to preclude the presence or addition of other components, units, modules, features or integers.

The term "consisting of … …" is intended to mean that it includes the specified component or components, unit or units, module or modules, feature or integer or integers, but not other components, units, modules, features or integers.

Use of the term "comprising" can also be viewed as including the meaning of "consisting essentially of … …" and can also be viewed as including the meaning of "consisting of … …" as appropriate, depending on the context.

The optional features listed herein may be used alone or in combination with one another where appropriate, particularly in the combinations listed in the appended claims. As set forth herein, optional features of each aspect or exemplary embodiment of the invention may also be applicable to all other aspects or exemplary embodiments of the invention, where appropriate. In other words, each aspect of the invention or optional features of the exemplary embodiments should be considered interchangeable and combinable between different aspects and exemplary embodiments by a person reading the present description.

Drawings

For a better understanding of the present invention, and to show how exemplary embodiments of the same may be carried into effect, reference will now be made, by way of example only, to the accompanying drawings, in which:

FIG. 1 schematically illustrates a perspective view of a track assembly according to an exemplary embodiment, including a sled according to an exemplary embodiment;

FIG. 2 schematically illustrates an end view of the track assembly of FIG. 1;

FIG. 3 schematically illustrates a side view of the track assembly of FIG. 1;

FIG. 4 schematically illustrates a plan view of the track assembly of FIG. 1;

FIG. 5 schematically illustrates a plan view of the track assembly of FIG. 1;

FIG. 6 schematically illustrates a longitudinal cross-sectional view of the track assembly of FIG. 5;

FIG. 7 schematically illustrates a longitudinal cross-sectional view of the track assembly of FIG. 5 in greater detail;

FIG. 8 schematically illustrates a side view of the track assembly of FIG. 1;

FIG. 9 schematically illustrates a cross-sectional view of the track assembly of FIG. 8 in a first configuration and a second configuration;

FIG. 10 schematically illustrates a cross-sectional view of the track assembly of FIG. 8 in more detail in a first configuration and a second configuration;

11A-11C schematically show a perspective view, an end view and a side view, respectively, of the guide of the trolley of FIG. 1 in more detail;

12A-12B schematically illustrate in more detail a partially exploded view and a partially transparent end view, respectively, of an attachment member for the sled of FIG. 1;

FIG. 13 schematically illustrates an end view of a track assembly according to an exemplary embodiment, including a sled according to an exemplary embodiment; and

fig. 14 schematically illustrates an end view of a track assembly according to an exemplary embodiment, including a sled according to an exemplary embodiment.

Detailed Description

Briefly, fig. 1-7 illustrate a track assembly 1 according to an exemplary embodiment, including a sled 100 according to an exemplary embodiment arranged in a first configuration. Fig. 8 to 10 show the trolley 100 arranged in use in a first configuration and a second configuration. Fig. 11A to 11C and 12A to 10B show details of the sled 100. Fig. 13 and 14 illustrate an alternative track assembly according to an exemplary embodiment, including a sled according to an exemplary embodiment.

Fig. 1 schematically shows a perspective view of a track assembly 1 according to an exemplary embodiment, including a trolley 100 according to an exemplary embodiment. Figure 2 schematically shows an end view of the track assembly 1 of figure 1. Fig. 3 schematically shows a side view of the rail assembly 1 of fig. 1. Fig. 4 schematically shows a plan view of the rail assembly 1 of fig. 1. Fig. 5 schematically illustrates a plan view of the track assembly of fig. 1. Figure 6 schematically illustrates a longitudinal cross-sectional view of the track assembly of figure 5, particularly in the plane B-B of figure 5. Figure 7 schematically shows a longitudinal cross-sectional view of the track assembly of figure 5 (particularly region B of figure 5) in more detail.

In particular, the trolley 100 is used for the track 10. The sled 100 includes: a frame 110, a set S of wheels 120 (including a first wheel 120A and a second wheel 120B) rotatably coupled to the frame 110, and an attachment member 130 coupled to the frame 110, the attachment member 130 for suspending a load W therefrom in use. The first wheel 120A is rotatable about a first axis A1 within a first plane P1 and the second wheel 120B is rotatable about a second axis A2 within a second plane P2. The first plane P1 and the second plane P2 define a line L. The sled 100 may be arranged in a first configuration with the attachment member 130 arranged at a first angular displacement D1 about the line L. The sled 100 may be arranged in a second configuration with the attachment member 130 arranged at a second angular displacement D2 about line L, wherein the first and second angular displacements D1 and D2 are different.

As described above, since the attachment member 130 is movable between the first configuration and the second configuration, lateral forces on the rail 10 may be reduced, for example, as compared to a fixed attachment member. In this way, the likelihood of the trolley 100 being bound and thus braking on the track is reduced. In this way, the likelihood of the user being injured and/or trapped may be reduced. In this way, user safety and/or sled reliability may be improved.

Furthermore, since the lateral forces on the track 10 may be reduced compared to a fixed attachment member 130, the number of wheels comprised in the set S of wheels 120 and/or the size of the wheels comprised in the set S of wheels 120 may be reduced, for example. Additionally and/or alternatively, the strength of the frame 110 may be reduced. In this manner, the weight and/or cost of the sled 100 may be reduced. Instead, an increased load W may be attached to the trolley 100.

Sliding vehicle

The trolley 100 is adapted for use with the track 10 and is arranged to roll on the track. Typically, the sled 100 is held on the track 10, for example by a set S of wheels 120, such that the sled 100 cannot be removed (i.e., disengaged) from the track 10 in use.

The sled 100 includes a frame 110, a set S of wheels 120 rotatably coupled to the frame 110, and an attachment member 130 coupled to the frame 110. That is, the frame 110 transfers the force due to the load W to at least one of the plurality of wheels in the set S of wheels 120, such as the first wheel 120A and/or the second wheel 120B. In this example, the frame 110 includes an open structure provided by, for example, one or more struts and/or one or more tethers. In this example, the frame 110 is made of welded aluminum plate (grade 5083) having a thickness of 5 mm. The frame comprises two end C-shaped

parts

110A, 110B, four rods 110C to 110F extending between them, a middle C-shaped part 110G between them, two brackets 110H, 110I connected to the rods 110C and 100F, and two

auxiliary attachment members

110J, 110K connected to the two end C-shaped

parts

110, 110B, respectively. In this example, the frame 110 includes a passage P through which the track 10 passes. The

auxiliary attachment members

110J, 110K are used for attachment of the handle and the auxiliary harness sling, respectively.

Wheel set

The sled 100 includes a set S of wheels 120 rotatably coupled to the frame 110, including a first wheel 120A and a second wheel 120B. In the drawings, the wheels of the set S of wheels 120 are shown generally out of contact with the track 10 for clarity. However, it will be appreciated that, in use, one or more wheels of the set S of wheels 120 are typically in contact with the track 10. For example, in use, one or more or all of the wheels of the subset S1 of wheels 120 (described below), including the first wheel 120A and the second wheel 120B, are typically in contact with the track 10. For example, in use, one or more or all of the subset S2 of wheels 120 and/or one or more or all of the subset S3 of wheels 120 (described below) are typically not in contact with the rail 10, are spaced apart from the rail 10 by a gap of about 5mm, but may be in contact with the rail 10 during yawing, pitching and/or rolling of the sled 100.

In this example, the first wheel 120A and the second wheel 120B are arranged to roll on an upper and/or lateral portion of the track 10, in particular on an upper and/or lateral portion of the tube 11 thereof, and thereby at least partially transfer weight due to the load W to the track 10 and/or transfer forces due to movements (e.g. pitch and/or yaw) of the load W to the track 10. In this example, the first wheel 120A and the second wheel 120B are disposed at the same end of the frame 110. In this example, the first wheel 120A and the second wheel 120B are arranged on opposite sides of the passageway P in the frame 110, whereby the first wheel 120A and the second wheel 120B are arranged on opposite sides of the track 10 in use.

In this example, the set S of wheels 120 includes a third wheel 120C and a fourth wheel 120D, as described with respect to the first wheel 120A and the second wheel 120B, respectively. In this example, third and

fourth wheels

120C, 120D are disposed at opposite ends of frame 110 from first and

second wheels

120A, 120B, first and

third wheels

120A, 120C are disposed on opposite sides of a channel in frame 110, and second and

fourth wheels

120B, 120D are disposed on opposite sides of a channel in frame 110.

In this example, the set S of wheels 120 is arranged to retain the trolley 100 on the track 10 such that the trolley 100 is not removed (i.e. disengaged) from the track 10 in use. In other words, the trolley 100 is tied up on the track, thereby improving safety.

In this example, the set S of wheels 120 is arranged to at least partially resist forces in two mutually orthogonal directions, for example due to the weight of the load W and/or pitch, roll and/or yaw of the trolley 100, whilst allowing movement of the trolley 100 in a third mutually orthogonal direction, for example downwards and/or upwards along the track 10.

Wheel set

In this example, the set S of wheels 120 includes a first subset S1 of the wheels 120, a first subset S1 includes a first wheel 120A, a second wheel 120B, and third and

fourth wheels

120C, 120D. In this example, the first subset S1 of wheels 120 is arranged to roll on one or more upper and/or lateral portions of the track 10 (in particular on the tube 11 thereof) and thereby at least partially transfer weight due to the load W to the track 10 and/or transfer forces due to movements (e.g. pitch and/or yaw) of the load W to the track 10. In this example, the first wheel 120A and the third wheel 120C are rotatably coupled to the first rod 110C of the frame 110. In this example, the second wheel 120B and the fourth wheel 120D are rotatably coupled to the second rod 110D of the frame 110.

In this example, the set S of wheels 120 includes a second subset S2 of wheels 120, the second subset S2 including a fifth wheel 120E, a sixth wheel 120F, a seventh wheel 120G, and an eighth wheel 120H. In this example, the second subset S2 of wheels 120 is arranged to roll on one or more lower and/or side portions of the track 10 (in particular on the tube 11 thereof), thereby at least partially transferring forces due to movements (e.g. pitch and/or yaw) of the load W onto the track 10. In this example, fifth and

seventh wheels

120E, 120G are rotatably coupled to third rod 110E of frame 110. In this example, the sixth wheel 120F and the eighth wheel 120H are rotatably coupled to the fourth rod 110F of the frame 110.

In this example, the set S of wheels 120 includes a third subset S3 of wheels 120, the third subset S3 including a ninth wheel 120I and a tenth wheel 120J. In this example, the third subset S3 of wheels 120 is arranged to roll on a lateral portion of the rail 10 (in particular on the flange 12 thereof), thereby at least partially transferring forces generated by the movement (e.g. rolling) of the load W onto the rail 10. In this example, a ninth wheel 120I is rotatably coupled to the first bracket 110H and a tenth wheel 120J is rotatably coupled to the second bracket 110I.

Wheel alignment

The first wheel 120A is rotatable about a first axis a1 within a first plane P1 and the second wheel 120B is rotatable about a second axis a2 within a second plane P2, wherein the first plane P1 and the second plane P2 define a line L.

In this example, the first axis a1 and the second axis a2 are inclined to each other, whereby the first plane P1 and the second plane P2 are inclined to each other. If the first plane P1 and the second plane P2 are inclined to each other, the line L is defined by the intersection of the first plane P1 and the second plane P2. In this example, line L is the intersection of first plane P1 and second plane P2. In this example, line L is the intersection of a first plane P1 and a second plane P2, and the track 10 comprises a cylindrical running surface defining a cylindrical axis, wherein line L is substantially coincident with the cylindrical axis in use.

In this example, the first axis a1 and the second axis a2 are tangent to a radius perpendicular to line L.

Wheel of vehicle

In this example, the first wheel 120A comprises a polyurethane roller having an outer diameter of 62mm, bonded to a deep groove ball bearing, such as SKF 6301ZZ deep groove ball bearing having a 12mm bore and a length of 12 mm.

In this example, the first wheel 120A is mounted on an axle, wherein the axle is fastened to the frame 110. In this example, the shaft is a bolt fastened to the frame 110 with a nut.

In this example, the first wheel 120A is a driven wheel (i.e., not driven).

The second wheel 120B is as described with respect to the first wheel 120A. Each wheel of the subset of the set S of wheels 120 is as described with respect to the first wheel 120A.

Attachment member

The trolley 100 comprises an attachment member 130, the attachment member 130 being coupled to the frame 110 for suspending a load W therefrom in use.

In this example, the attachment member 130 is releasably coupled to the frame 110. In this example, releasing the attachment member 130 from the frame 110 requires the use of a tool. In this example, the attachment member 130 includes a fastener, such as a pin fastener, a cotter pin (also referred to as a cotter pin, cotter key, or cotter pin), a locking ring, a hook latch, or a clamp, to limit release of the attachment member 130 from the frame 110. In this way, unintentional or intentional release of the attachment member 130 during use may be avoided, thereby improving safety. In this example, the attachment member 130 includes a D-shackle that is closed with an anchor bolt.

Guide piece

The frame 100 includes guides 112, as described below with reference to fig. 11A-11C.

Roller wheel

In this example, the attachment member 130 includes a roller 132 arranged to roll on the guide 112. The related attachment member 130' is described below with reference to fig. 12A to 12B.

In this example, the roller 132 is a grooved roller 132 having a circumferential arc groove, and the guide 112 has a circular cross section. In this example, the radius of the groove is larger than the radius of the guide 112, for example in the range of 1% to 20%, preferably in the range of 3% to 10%.

In this example, the attachment member 130 comprises a D-shaped shackle 133 closed with an anchor bolt 134 and a slotted roller 132 having a circumferential arc groove, wherein the attachment member 130 comprises two

ball bearings

135A, 135B, wherein the slotted roller 132 is mounted on the anchor bolt 134 between the legs of the D-shaped shackle 133, spaced from the shackle legs by two

spacers

136A, 136B.

In this example, the attachment member 130 may rotate about a normal to the line L. In this way, twisting of the load W relative to the trolley 100 can be accommodated.

In this example, the roller 132 is formed of SAE 316 type stainless steel.

First and second configurations

Fig. 8 schematically shows a side view of the rail assembly 1 of fig. 1. Figure 9 schematically shows a cross-sectional view of the track assembly 1 of figure 8 (particularly in the a-a plane of figure 8) in a first configuration and a second configuration. Figure 10 schematically shows a cross-sectional view of the track assembly 1 of figure 8 (particularly in region a of figure 9) in a first configuration and a second configuration in more detail. In particular, fig. 9 and 10 show the attachment member 130 disposed at a first angular displacement D1 about line L and the attachment member 130 disposed at a second angular displacement D2 about line L. That is, the same attachment member 130 is shown at two different angular displacements D1 and D2. It should be appreciated that the magnitude and/or direction of the load W at the two different angular displacements D1 and D2 will be different.

In this example, the height or elevation of the attachment member 130 at the second angular displacement D2 is greater than the height or elevation at the first angular displacement D1. That is, the second gravitational potential energy of the load W when the trolley 100 is arranged in the second configuration is greater than the first gravitational potential energy of the load W when the trolley 100 is arranged in the first configuration. That is, work must be done to move the attachment member 130 from the first configuration to the second configuration. In this way, the movement of the load W, and thus the movement of the attachment member 130 transverse to the line L, may be controlled, e.g. slowed down.

In this example, the trolley 100 is arranged to move from the first configuration to the second configuration due to forces transverse to the line L (i.e. lateral forces, transverse forces) which are at least partially due to movement of the load W transverse to the line L.

In this example, the attachment member 130 is arranged to move in an arc (e.g., increasing height or elevation) about the line L from the first angular displacement D1 to the second angular displacement D2. In this example, the track 10 comprises a cylindrical running surface defining a cylindrical axis, wherein the line L is substantially coincident with the cylindrical axis in use, the attachment member 130 is arranged to move in an arc about the line L from a first angular displacement D1 to a second angular displacement D2, and the arc is concentric with the cylindrical running surface.

Guide piece

Fig. 11A to 11C schematically show a perspective view, an end view and a side view, respectively, of the guide 112 of the trolley 100 of fig. 1 in more detail.

In this example, the sled 100 includes a guide 112 coupled to the frame 110, the guide 112 arranged to guide 112 the attachment member 130 between the first configuration and the second configuration. In this example, the guide 112 includes an arcuate portion that subtends an angle of about 100 °. In this example, the guide 112 has a circular cross-section, whereby the guide 112 comprises a round rod with a diameter of 12 mm. In this example, the guide 112 is formed of SAE 316 type stainless steel. At each end of the round rod, a bracket is provided, which includes a counter bore of 8mm diameter for fastening the guide 112 to the

rods

110E and 110F using a counter bolt and nut (allen wrench).

Roller wheel

Fig. 12A to 12B schematically show a partially exploded view and a partially transparent end view, respectively, of an attachment member 130' for the sled of fig. 1 in more detail. The attachment member 130' is generally as described with respect to the attachment member 130. The attachment member 130 includes a D-shackle 133 closed with an anchor bolt 134. In contrast, the attachment member 130 ' includes a pin shackle 133 ', the pin shackle 133 ' being closed with an anchor bolt 134 ' and a cotter pin 138 ', and further includes a fixing nut 137 ' in addition to the cotter pin 138 '.

In this example, the attachment member 130' includes a roller 132 arranged to roll on the guide 112. In this example, the roller 132 includes two bearing deep

groove ball bearings

135A, 135B. In this example,

bearings

135A, 135B are sealed. In this example, the attachment member 130' includes two

shims

136A, 136B.

In this example, the roller 132 is a grooved roller 132 having a circumferential arc groove, and the guide 112 has a circular cross section. In this example, the radius of the groove is greater than the radius of the guide 112, in the range of 1% to 20%.

In this example, the attachment member 130 ' includes a pin shackle 133 ' and a slotted roller 132, the pin shackle 133 ' being closed with an anchor bolt 134 ' and a cotter pin 138 ', and including a retaining nut 137 ' in addition to the cotter pin 138 ', the slotted roller 132 having a circumferential arc-shaped groove, wherein the slotted roller 132 includes two

ball bearings

135A, 135B, the slotted roller 132 being mounted on the anchor bolt 134 ' between the two legs of the shackle 133 ', spaced from the shackle legs by two

spacers

136A, 136B.

Track assembly

The track assembly 10 includes a track 10 and a sled 100.

In this example, the track 10 is a monorail 10 (i.e., a single track 10).

In this example, the track 10 comprises a cylindrical running surface defining a cylindrical axis, wherein, in use, the line L substantially coincides with the cylindrical axis provided, for example, by a tube 11 having a circular cross-section, and the track 10 comprises a longitudinal flange 12 perpendicular to the tube 11 (i.e. standing on the tube 11), the longitudinal flange 12 extending continuously along the tube 11. In this example, the tube 11 has an outer diameter of 60mm and a wall thickness of 3 mm. In this example, the flange 12 is welded to the tube 11, for example continuously or intermittently.

In this example, the track 10 is made of a material complying with EN 10025: section 2: grade 2004S 235 steel. In this example, the rail 10 is painted.

While preferred embodiments have been shown and described, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the scope of the invention as defined in the following claims and as described above.

Fig. 13 schematically illustrates an end view of a track assembly according to an exemplary embodiment, including a sled 200 according to an exemplary embodiment.

The track assembly 2 and trolley 200 are generally as described with respect to the track assembly 1 and trolley 100, respectively. Like reference numerals refer to like features and, for the sake of brevity, the description will not be repeated. The track 10 is as previously described. Unlike the sled 100, the sled 200 includes a mechanical link 240, the mechanical link 240 is coupled to the frame 210, and the attachment member 230 is coupled to the mechanical link 240. In this example, the mechanical linkage 240 comprises a planar quadrilateral linkage.

Fig. 14 schematically shows an end view of a track assembly 3 according to an exemplary embodiment, including a trolley 300 according to an exemplary embodiment. In general

Track assembly 3, track 30 and trolley 300 are substantially as described with respect to track assembly 1, track 10 and trolley 100 respectively. Like reference numerals refer to like features and, for the sake of brevity, the description will not be repeated. In this example, the track comprises a U-shaped channel 31 and a flange 32. Unlike sled 100, sled 300 does not include a second subset of wheels, and frame 310 is modified accordingly. Unlike sled 100, sled 300 includes an attachment member 330 rotatably coupled to frame 310. In this example, the attachment member 330 is arranged to rotate about the line L, whereby, in a first configuration, the attachment member 330 is arranged to rotate about the line L by a first angle, and whereby, in a second configuration, the attachment member 330 is arranged to rotate about the line L by a second angle, wherein the first angle rotation and the second angle rotation are different.

In summary, a sled, a track assembly and a kit of parts for a track assembly are described. The trolley comprises an attachment member movable between a first configuration and a second configuration, whereby lateral forces on the track may be reduced, for example compared to a fixed attachment member. In this way the possibility of the trolley becoming bound to the track and thus braked is reduced. In this way, the likelihood of the user being injured and/or trapped may be reduced. In this way, user safety and/or sled reliability may be improved. Further, ride smoothness and ride quality can be improved.

It is noted that all documents and documents filed concurrently with or previous to the specification of this application are hereby disclosed for public reference with this specification and the contents of all such documents and documents are incorporated herein by reference.

All of the features disclosed in this specification (including any accompanying claims and drawings) and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of the foregoing embodiments. The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims

1. A sled for a track, the sled comprising:

a frame;

wherein the first plane and the second plane define a line;

wherein the sled is arrangeable at:

2. The pulley of claim 1, wherein the line is an intersection of the first plane and the second plane.

3. A tackle as claimed in any one of the preceding claims, wherein the attachment member is arranged to move in an arc about the line from the first angular displacement to the second angular displacement.

4. A tackle as claimed in any one of the preceding claims, including a guide coupled to the frame, the guide being arranged to guide the attachment member between the first configuration and the second configuration.

5. A tackle as claimed in claim 4, wherein the attachment member includes a roller arranged to roll on the guide.

6. A tackle as claimed in claim 5, wherein the roller is a slotted roller and/or the guide has a circular cross-section.

7. A tackle as claimed in any one of the preceding claims, wherein the attachment member is rotatable about a normal to the line.

8. A tackle as claimed in any one of the preceding claims, wherein the first and second wheels are planar wheels.

9. A tackle as claimed in any one of the preceding claims, wherein the first axis and/or the second axis is tangential to a radius that is perpendicular to the line.

10. A tackle as claimed in any one of the preceding claims, wherein the set of wheels includes three or more wheels.

11. A track assembly comprising a track and a trolley according to any one of claims 1 to 10.

12. The track assembly according to claim 11, wherein the track comprises a non-linear portion, such as a curved portion.

13. The track assembly according to any one of claims 11 to 12, wherein the track is a monorail.

14. The track assembly according to any one of claims 11 to 13, wherein the track comprises a cylindrical running surface defining a cylindrical axis, wherein the line is substantially coincident with the cylindrical axis in use.

15. The track assembly according to any one of claims 11 to 14, wherein the track comprises a longitudinal flange.