Patent Application
20160362284
The teachings described herein relate generally to a mobile lifting apparatus for raising and lowering a work platform that is sized to accommodate one or more persons in a standing position.
WO97/15522 (White et al.) discloses a movable cage assembly provided for use in conjunction with a portable personnel lift. The personnel lift has a multi-sectional telescoping mast which moves between a lower, retracted position where the cage assembly is below the top of the mast and an elevated position where the movable cage assembly is raised above the top of the mast to eliminate work envelope obstructions by the mast. A cage support beam is carried by the central mast section and the cage assembly is movable on the cage support beam between a lower position which provides ground level entry when the mast is retracted and a raised position wherein the cage is above the top of the mast. A clamshell-type cage assembly is also provided wherein the upper safety rail pivots between a raised position which facilitates easy entry into the cage wherein the user does not have to stoop or use either hand to hold the cage open. The safety rail is then pulled downwardly by the user once he has entered the cage.
U.S. Pat. No. 4,638,887 (Kishi) discloses an elevating apparatus that includes a base such as a mobile chassis, a platform, a telescopic boom assembly connecting the base and the platform together, the telescopic boom assembly being composed of a plurality of telescopically coupled booms axially aligned with each other, at least one first hydraulic cylinder disposed in the telescopic boom assembly for extending and contracting the telescopic boom assembly, a pair of second parallel hydraulic cylinders operatively coupled between the telescopic boom assembly and the base for tilting the telescopic boom assembly with respect to the base, a pair of parallel third hydraulic cylinders operatively coupled between the telescopic boom assembly and the platform for keeping the platform substantially parallel to the base, and a hydraulic control system for operating the first, second, and third hydraulic cylinders in synchronism to move the platform toward and away from the base in a substantially perpendicular relation to the base while the platform is stably maintained parallel to the base.
EP 244,060 (Ream et al.) discloses a pedestal scaffold having a base member on which is mounted a mast bearing a work platform and comprising a plurality of telescopically nested mast sections which are substantially rectangular in cross section. Means for extending the mast upwardly by relative telescopic displacement of the mast sections are provided. The scaffold is characterised in that at least some said mast sections are thin-walled tubes of sheet metal with rounded corners, each being provided with at least one stiffening rib extending longitudinally in a side wall thereof, a set of inwardly projecting corner slide blocks having respective inner surfaces complementing the shape of and adapted to slide against outer corner surfaces of an inwardly adjacent mast section and a set of outwardly projecting corner slide blocks having respective outer surfaces complementing the shape of and adapted to slide against inner corner surfaces.
This summary is intended to introduce the reader to the more detailed description that follows and not to limit or define any claimed or as yet unclaimed invention. One or more inventions may reside in any combination or sub-combination of the elements or process steps disclosed in any part of this document including its claims and figures.
Referring to one broad aspect of the teachings disclosed herein, a mobile lifting apparatus for raising and lowering one or more persons may include a bottom tower section. The bottom tower section may have a first bottom sidewall and an opposing second bottom sidewall that is horizontally spaced apart from the first bottom sidewall in a lateral direction. The first bottom sidewall may have a first laterally inner surface and a first wall length in a longitudinal direction that is generally horizontal and orthogonal to the lateral direction. The second bottom sidewall may have a second laterally inner surface laterally spaced apart from the first inner surface by a bottom inner width and a second wall length in the longitudinal direction. A top tower section may be coupled to, and be vertically translatable relative to, the bottom tower section. The top tower section may include a top carriage sized to fit between the first bottom sidewall and the second bottom sidewall. A work platform may be coupled to, and may be vertically translatable with, with the top carriage. The work platform may include a generally horizontal work surface which may have a first surface portion. The first surface portion may overlie the top carriage and may be sized to accommodate at least one person standing on the first surface portion. The first surface portion may have a first surface portion length in the longitudinal direction that is less than the first wall length and a first surface portion width in the lateral direction that is less than the bottom inner width. An elevating assembly may be operable raise and lower the top tower section relative to the bottom tower section. The top tower section may translatable to a lowered position in which the top carriage and the first surface portion are disposed laterally between the first and second bottom sidewalls. The work surface may include a second surface portion extending longitudinally outwardly from the first surface portion. When the top tower section is in the lowered position the second surface portion may extend longitudinally outboard the first and second bottom side walls.
The top tower section may include a first top sidewall extending from the top carriage and an opposing second top sidewall laterally spaced apart from the first top sidewall. The first surface portion may be disposed laterally between the first and second top sidewalls.
The first and second bottom sidewalls may at least partially bound a bottom tower section interior and when the top tower section is in the lowered position the top tower section may be at least substantially nested within the bottom tower section interior.
The first surface portion length that may be at least about 45 cm and the first surface portion width may be at least about 45 cm.
The lifting apparatus may have an overall apparatus width in the lateral direction. The first bottom sidewall may have a first laterally outer surface, the second bottom sidewall may have a second laterally outer surface laterally spaced apart from the first laterally outer surface by a tower outer width that is substantially equal to the overall apparatus width.
The lifting apparatus may be sized to fit through a standard doorway.
The overall apparatus width may be equal to or less than a width of a standard doorway, and may be equal to or less than about 81 cm.
When the top tower section is in the lowered position the lifting apparatus may have an overall apparatus height in the vertical direction that is less than the height of a standard doorway, and may be equal to or less than about 205 cm.
The lifting apparatus may include a first wheel assembly and a second wheel assembly longitudinally spaced apart from the first wheel assembly by a wheel assembly spacing distance. The first and second wall lengths may be substantially equal to the wheel assembly spacing distance.
The bottom tower section may have a bottom front face and a bottom rear face longitudinally spaced apart from the front face, and the first and second bottom sidewalls may extend longitudinally between the bottom front and rear faces. A lower portion of the front face may include a bottom front wall extending laterally between the first and second bottom sidewalls and an upper portion of the bottom front face may be open. When the top tower section is in the lowered position the work platform may overhang the bottom front wall and extend longitudinally through the open upper portion of the bottom front face.
Configuring the lifting apparatus such that the work surface of the work platform can be partially nested within the tower sections and can be lowered to an elevation that is lower than the upper edges of the bottom tower section may allow the step-in or entry height of the work platform to be maintained within a desired range, such as, for example, between about 70 cm and about 100 cm, and optionally between about 88 cm and about 94 cm. In the illustrated example, the entry height of the work platform is about 90 cm.
Optionally, the bottom tower section may include a bottom front cover that is moveably coupled to the bottom tower section and is movable from a first stowed position in which the bottom front cover is generally clear of the open upper portion of the front face, and a first deployed position in which the bottom front cover generally covers all or a part of the open upper portion of the bottom front face when the tower is at least partially extended.
The bottom front cover may be coupled to the top tower section so that raising the top tower section relative to the bottom tower section moves the bottom front cover toward the first deployed position.
The bottom front cover may include a first front cover panel and a second front cover panel. The first and second front cover panels may be vertically translatable relative to the first and second bottom sidewalls between a respective front panel lowered position corresponding to the first stowed position and in which the panels generally overlap the bottom front wall in horizontally offset relation, and a respective front panel raised position corresponding to the first deployed position and in which the first and second front cover panels are vertically displaced.
The first and second bottom sidewalls may have respective sidewall thicknesses and the bottom front wall may have a front wall thickness that is at least about twice the sidewall thicknesses.
A lower portion of the bottom rear face may include a bottom rear wall extending laterally between the first and second bottom sidewalls and an upper portion of the bottom rear face may be open. When the top tower section is in the lowered position the work platform may overhang the bottom rear wall and may extend longitudinally through the open portion of the bottom rear face.
The bottom tower section may include a bottom rear cover that is moveably coupled to the bottom tower section and is movable from a second stowed position in which the bottom rear cover is generally clear of the open portion of the bottom rear face and a second deployed position in which the bottom rear cover generally covers the open portion of the bottom rear face.
The bottom rear cover may be movable with the top tower section so that raising the top tower section relative to the bottom tower section moves the bottom rear cover toward the second deployed position.
The bottom rear cover may include a first rear cover panel and a second rear cover panel. The first and second rear cover panels may be vertically translatable relative to the first and second bottom sidewalls between a respective rear panel lowered position corresponding to the second stowed position and in which the rear panels generally overlap the bottom rear wall in horizontally offset relation, and a respective rear panel raised position corresponding to the second deployed position and in which the first and second rear cover panels are vertically displaced.
At least one intermediate tower section may be disposed between the bottom tower section and the top tower section. Each intermediate tower section may be sized to fit laterally between the first and second bottom sidewalls and may be vertically translatable relative to the bottom tower section. Each intermediate tower section may include a respective intermediate section first sidewall and an opposing respective intermediate section second section laterally spaced part from the respective intermediate section first sidewall. The top tower section may be coupled to and vertically translatable relative to an upper most one of the at least one intermediate tower section.
Each intermediate tower section may include a respective intermediate section front face and an opposing respective intermediate section rear face longitudinally spaced apart from the respective intermediate section font face and the respective intermediate section first and second sidewalls extending longitudinally between the respective intermediate section front and rear faces. A lower portion of each respective intermediate section front face may include a respective intermediate section bottom wall extending laterally between the respective intermediate section first and second sidewalls and an upper portion of each respective intermediate section front face may be open. When the top tower section is in the lowered position the open portion of each respective intermediate section front face may be vertically aligned with the open portion of the bottom front face and the work platform may overhang each respective intermediate section front wall and extends longitudinally through the open portion of each respective intermediate section front face.
Each intermediate tower section may include a respective intermediate section front cover that is moveably coupled to the respective intermediate tower section and is movable from a stowed position in which it is spaced apart from the open portion of the respective intermediate section front face, and a deployed position in which each respective intermediate section front cover generally covers the open portion of each respective intermediate section front face.
The first and second bottom sidewalls may include respective upper edges and when the top tower section is in the lowered position, the first surface portion may be disposed at a lower elevation than the first and second bottom sidewall upper edges.
In accordance with some aspects of the teachings disclosed herein, a lifting apparatus for raising and lowering one or more persons may include a bottom tower section including a first bottom sidewall and an opposed second bottom sidewall spaced apart from the first bottom sidewall in a lateral direction. The first and second bottom sidewalls may extend generally vertically and the bottom tower section may include a bottom track extending vertically and supported by the first and second bottom sidewalls. At least a first intermediate tower section may be sized to fit laterally between the first and second bottom walls and may be vertically translatable relative to the bottom tower section. The first intermediate tower section may include a first carriage that has a first side adjacent the first bottom sidewall and a second side adjacent the second bottom sidewall. The first carriage may be supported by the bottom track and may be vertically translatable along the bottom track. The first carriage may be constrained by the bottom track so that the first and second sides vertically translate in unison whereby tilting of the first intermediate tower section relative to the bottom tower section in the lateral direction is inhibited. A top tower section may be coupled to and may vertically translatable relative to the first intermediate tower section. A work platform may be affixed to and may be translatable with the top tower section. The work platform may include a generally horizontal work surface. An elevating assembly may be operable to raise and lower the first intermediate tower section and the top tower section relative to the bottom tower section.
The first carriage may include a first end extending between the first and second sides of the first carriage and a second end longitudinally spaced apart from the first end. The first carriage may be constrained by the bottom track so that the first and second ends vertically translate in unison, whereby tilting of the first intermediate tower section relative to the bottom tower section in the longitudinal direction is inhibited.
The first intermediate tower section may include a first section first sidewall adjacent the bottom first sidewall and a first section second sidewall adjacent the bottom second sidewall and a first section track extending vertically and supported by the first section first and second sidewalls. The top tower section may include a top carriage supported by the first section track and vertically translatable along the first section track. The top carriage may include a first side adjacent the first section first sidewall, a second side adjacent the first section second sidewall, a first end extending between the first and second sides and a second end longitudinally spaced apart from the first end. The top carriage may be constrained by the first section track so that the first side, second side, first end and second end of the top carriage vertically translate in unison whereby tilting of the top tower section relative to the first intermediate tower section in the longitudinal direction and in the lateral direction is inhibited.
The first intermediate tower section may include a first section first sidewall adjacent the bottom first sidewall and a first section second sidewall adjacent the bottom second sidewall and a first section track extending vertically and supported by the first section first and second sidewalls. A second intermediate tower section may have a second carriage supported by the first section track and vertically translatable along the first section track. The second carriage may include a first side adjacent the first section first sidewall, a second side adjacent the first section second sidewall, a first end extending between the first and second sides and a second end longitudinally spaced apart from the first end. The second carriage may be constrained by the first section track so that the first side, second side, first end and second end of the second carriage vertically translate in unison whereby tilting of the second intermediate tower section relative to the first intermediate tower section in the longitudinal direction and in the lateral direction is inhibited.
The second intermediate tower section may include a second section first sidewall adjacent the first section first sidewall and a second section second sidewall adjacent the first section second sidewall and a second section track extending vertically and supported by the second section first and second sidewalls. The top tower section may include a top carriage supported by the second section track and vertically translatable along the second section track. The top carriage may include a first side adjacent the second section first sidewall, a second side adjacent the second section second sidewall, a first end extending between the first and second sides and a second end longitudinally spaced apart from the first end. The top carriage may be constrained by the second section track so that the first side, second side, first end and second end of the top carriage vertically translate in unison whereby tilting of the top tower section relative to the second intermediate tower section in the longitudinal direction and in the lateral direction is inhibited.
The bottom track may include at least one bottom guide member connected to each of the first and second bottom sidewalls, and the first carriage may include at least one first carriage roller engaging each bottom guide member, and wherein each of the first carriage rollers are linked together to rotate in unison with each other.
The first section track may include at least one first section guide member connected to each of the first section first and second sidewalls, and the second carriage may include at least one second carriage roller engaging each first section guide member. Each of the second carriage rollers may be linked together to rotate in unison with each other.
The second section track may include at least one second section guide member connected to each of the second section first and second sidewalls, and the top carriage may include at least one top carriage roller engaging each second section guide member. Each of the top carriage rollers may be linked together to rotate in unison with each other.
The bottom, first section and section guide members may include vertically extending racks. The first carriage, second carriage and top carriage rollers may include pinions engaging respective ones of the racks.
The elevating assembly may include a lift actuator coupled to the first carriage rollers to drive rotation of the first carriage rollers. Driving the first carriage rollers in a first direction may raise the first intermediate tower section relative to the bottom tower section.
The lift actuator may include a first motor coupled to the first carriage rollers. The first motor may be mounted on the first carriage and may be movable with the first carriage.
The lift actuator may include a second motor be coupled to the second carriage rollers to drive rotation of the second carriage rollers. Driving the second carriage rollers in the first direction may raise the second intermediate tower section relative to the first intermediate tower section.
The second motor may be mounted on the second carriage and may be movable with the second carriage.
The second motor may be operable independently from the first motor.
The lift actuator may include a third motor coupled to the top carriage rollers to drive rotation of the top carriage rollers. Driving the top carriage rollers in the first direction may raise the top tower section relative to the second intermediate tower section.
The third motor may be mounted on the top carriage and may be movable with the top carriage.
The third motor may be operable independently from at least one of the first motor and the second motor.
The lift actuator may be operable to simultaneously drive the first carriage rollers, the second carriage rollers and the top carriage rollers whereby the first intermediate tower section, second intermediate tower section and top tower section are raisable in unison.
Each of the first intermediate, second intermediate and top carriages may include a respective gear train linking the respective carriage rollers.
At least one of the first intermediate, second intermediate and top carriage gear trains may be self-braking and may resist rotating in a second direction that is opposite the first direction.
The lifting apparatus may include at least one controller communicably linked to the first motor, second motor and third motor to control operation of the first motor, second motor and third motor.
The at least one controller may include a first controller mounted on and movable with the first carriage for controlling the first motor, a second controller mounted on and movable with the second carriage for controlling the second motor and a third controller mounted on and movable with the top carriage for controlling the third motor.
The first motor, second motor and third motor may be electric motors and the lift actuator may be free from hydraulic actuators.
The first and second bottom sidewalls may each include at least one bracing member to resist deflection of at least one of the first and second bottom sidewalls and the bottom track.
The first bottom sidewall may include a generally vertically extending first wall front edge and a generally vertically extending first wall rear edge longitudinally spaced apart from the first wall front edge, and the at least one bracing member on the first bottom sidewall may include a first front upright adjacent the first wall front edge and a first rear upright adjacent the first wall rear edge.
The bottom guide members may include a first front rack attached to the first front upright and a first rear rack attached to the first rear upright.
The work surface may have a first surface portion, the first surface portion overlying the top carriage and being sized to accommodate at least one standing person and wherein the top tower section is translatable to a lowered position in which the top carriage and the first surface portion are disposed laterally between the first and second bottom sidewalls.
In accordance with some aspects of the teachings disclosed herein, a mobile lifting apparatus for raising and lowering one or more persons may include a tower assembly having a bottom tower section including a first bottom sidewall and an opposed second bottom sidewall spaced apart from the first bottom sidewall in a lateral direction. The first and second bottom sidewalls may extend generally vertically and the bottom tower section may include a bottom track extending vertically and supported by the first and second bottom sidewalls. At least a first intermediate tower section may be sized to fit laterally between the first and second bottom walls and vertically translatable relative to the bottom tower section. The first intermediate tower section may include a first carriage having a first side adjacent the first bottom sidewall and a second side adjacent the second bottom sidewall, the first carriage is supported by the bottom track and vertically translatable along the bottom track and is constrained by the bottom track so that the first and second sides vertically translate in unison whereby tilting of the first intermediate tower section relative to the bottom tower section in the lateral direction is inhibited. A top tower section may be coupled to and vertically translatable relative to the first intermediate tower section, and a work platform coupled to and translatable with the top tower section. The work platform may include a generally horizontal work surface. An elevating assembly may be operable to raise and lower the first intermediate tower section and the top tower section relative to the bottom tower section. The apparatus may also include a first wheel assembly for rollingly engaging a surface and a second wheel assembly for rollingly engaging the surface. The second wheel assembly may be horizontally spaced apart from the first wheel assembly. A lower portion of the bottom tower section may be disposed horizontally between and secured to the first and second wheel assemblies.
Each of the first and second wheel assemblies comprises at least one wheel rotatable about a respective axis and a horizontal plane containing a bottom face of the bottom tower assembly is at an elevation below each wheel axis.
The first wheel assembly may include at least two steerable wheels each pivotable about a respective vertical steering axis and each rotatable about a respective horizontal wheel axis, and wherein a horizontal plane intersecting a lower portion of the bottom track is at an elevation below each horizontal wheel axis.
The first wheel assembly may be mounted to a front face of the bottom tower section, and the second wheel assembly may mounted to a rear face of the bottom tower section that is opposite and longitudinally spaced apart from the front face.
The first wheel assembly may include at least two steerable wheels and at least one electric steering motor to steer the steerable wheels.
The first wheel assembly may include at least one electric propulsion motor to drive rotation of at least one of the steerable wheels.
The first intermediate tower section may translatable to a lowered position relative to the bottom tower section in which the first carriage is less than 60 cm above the surface.
The first intermediate tower section may be translatable to a lowered position in which the work surface is less than about 100 cm above the surface.
The first and second wheel assemblies may be adjustable to raise and lower the tower assembly relative to the surface. When the first intermediate tower section and the top tower section are raised relative to the bottom tower section the first and second wheel assemblies may lower the tower assembly so that a bottom face of the bottom tower section is less than about 2 cm above the surface.
The bottom track may include a plurality of racks, each rack extending along the length of the vertical extent of the bottom section, and each rack may have a lower rack end that is disposed at an elevation below the axis of rotation of the steerable wheels.
According to some aspects, the teaching herein discloses a tower assembly that can be extended and retracted to raise and lower a platform (or other payload carrier) supported by the tower assembly. The tower assembly includes a bottom tower section and a top tower section. The bottom tower section can include a bottom track, and the top tower section can include a top carriage that is supported by, and translatable along, the bottom track. Optionally, the tower assembly can include at least one intermediate tower section, and each intermediate tower section can include (i) a respective intermediate carriage for translatably engaging the track of a next-lower tower section, and (ii) a respective intermediate track mounted in fixed relation to the respective intermediate carriage for translatably supporting the carriage of the next higher tower section.
In an example with a single intermediate tower section, the intermediate tower section may include an intermediate carriage engaged with the bottom track of the bottom section. The intermediate section may have an intermediate track mounted to the intermediate carriage to translate with the carriage, and the top carriage of the top tower section may have rollers engaged with, and translatable along, the intermediate track.
In an example with two intermediate tower sections, the first intermediate tower section may include a first intermediate carriage engaged with the bottom track of the bottom section. The first intermediate section may have a first intermediate track mounted to the first intermediate carriage to translate with the first intermediate carriage. The second intermediate section may have a second intermediate carriage engaged with the first intermediate track of the first intermediate section. The second intermediate section may have a second intermediate track mounted to the first intermediate carriage to translate with the second intermediate carriage. The top carriage of the top tower section may have rollers engaged with, and translatable along, the second intermediate track.
Each track may comprise a respective set of toothed racks, and the respective carriage supported by each respective rack may comprise a set of rollers in the form of toothed pinions each engaged with a respective rack. The engagement of the pinion teeth with the rack teeth requires that vertical translation of the pinion along the rack (even a small amount of translation) is associated with a particular amount of rotation of the pinion. The engagement of the corresponding teeth may inhibit “slipping” of the carriage along the rack without rotation of the pinion.
Furthermore, the rollers of each carriage may be coupled together by, for example, a transmission system including one or more shafts and/or one or more gears, such that all the pinions of any one particular carriage must rotate in unison. No pinion of any one particular carriage can rotate without all the other pinions rotating the same amount. This can inhibit tilting of the carriage relative to the track, since in order to tilt, one side of the carriage would typically need to translate more or less than another side of the carriage. The presence of the pinions at longitudinally and laterally spaced-apart locations of the carriage (e.g. four pinions each at respective corners of a rectangular-shaped carriage and constrained to rotate in unison) facilitates equal vertical translation of all portions of the carriage. The constrained carriage helps to provide a telescoping-like tower structure that has a satisfactory degree of lateral, anti-tilt, stability, independent of overlapping a lower portion of a next-higher tower section with an upper portion of a next-lower tower section.
The drawings included herewith are for illustrating various examples of articles, methods, and apparatuses of the teaching of the present specification and are not intended to limit the scope of what is taught in any way.
In the drawings:
Various apparatuses or processes will be described below to provide an example of an embodiment of each claimed invention. No embodiment described below limits any claimed invention and any claimed invention may cover processes or apparatuses that differ from those described below. The claimed inventions are not limited to apparatuses or processes having all of the features of any one apparatus or process described below or to features common to multiple or all of the apparatuses described below. It is possible that an apparatus or process described below is not an embodiment of any claimed invention. Any invention disclosed in an apparatus or process described below that is not claimed in this document may be the subject matter of another protective instrument, for example, a continuing patent application, and the applicants, inventors or owners do not intend to abandon, disclaim or dedicate to the public any such invention by its disclosure in this document.
Referring to
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The bottom tower section 200 has a front face 220 and a rear face 222 longitudinally spaced apart from the front face 220. In the illustrated example the first and second bottom sidewalls 202a and 202b extend continuously between the bottom front and rear faces 220 and 222. In this example, the front face 220, rear face 222 and the first and second bottom sidewalls 202a and 202b co-operate to form a lower periphery and generally define an interior 224 of the bottom tower section 200.
Referring also to
Optionally, the bottom front and rear walls 226 and 230 may have a wall thickness 294 that is greater than the thickness 295 of the bottom sidewalls 202a and 202b. Referring to
Optionally, some or all of the tower sections may be provided with one or more bracing members to help resist lateral deflection of the respective sidewalls. For example, the bottom tower section 200 may be provided with at least one bracing member 261 to help limit deflection of the first and second bottom sidewalls 202a and 202b. The strength and configuration of the bracing members may be selected based on their expected loading. For example, the bracing member on the bottom tower section 200 may be stronger than the bracing member on the top tower section 500, as the top tower section 500 does not need to support as much weight as the bottom tower section 200. Referring to
In the illustrated example, the first intermediate tower section 300, the second intermediate tower section 400 and the top tower section 500 have some structural similarities with the bottom tower section 200, and like features are identified using like reference characters incremented by 100, 200 and 300 respectively.
Referring to
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Referring to
In the illustrated example, the second intermediate tower section 400 is generally similar to the first intermediate tower section 300 and is sized to fit laterally between the first and second sidewalls 302a and 302b of the first intermediate tower section. Referring to
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Optionally, the top tower section 500 may also include top sidewalls extending generally upwardly from the top carriage 550 and surrounding at least a portion of the work platform 104. Referring to
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Also, in the example illustrated, when the tower assembly 102 is retracted, both the top carriage 550 and the first surface portion 118 of the work surface 106 are disposed at a lower elevation than the upper edges 214a and 214b of the sidewalls 202a and 202b. Referring to
To fit within the interior 224 of the bottom tower section 200 the first surface portion 118 has a first surface portion length 122 that is less than the sidewall lengths 208a and 208b, and a first surface portion 124 width that is less than the bottom inner width 210. In the illustrated example, the first surface portion 118 is also disposed between the top sidewalls 502a and 502b and accordingly the first surface portion length 122 is substantially equal to the top sidewall lengths 508a and 508b, and the first surface portion width 124 is equal to the top tower section inner width 510. The first surface portion length 122 may be any suitable length (for example between about 30 cm and about 600 cm), and in the example illustrated is about 45 cm. The first surface portion width 124 may be any suitable width (for example between about 30 cm and about 300 cm), and in the example illustrated is about 45 cm.
As noted herein, providing front faces 220, 320, 420 and 520 of the tower sections 200, 300, 400 and 500 with upper portions that are generally free from fixed walls facilitates retraction of the work platform 104 into the interior of the tower sections in cases where the work platform has an overall work platform length 114 that is greater than the bottom sidewall lengths 208a and 208b (i.e. protrudes beyond one or both ends of the tower periphery). Referring to
To help facilitate extension and retraction of the tower, the tower sections 300, 400 and 500 are configured to translate vertically relative to each other. In this configuration, constraining the movement for the tower sections 300, 400 and 500, so that they are permitted to translate vertically but are inhibited from tilting in at least one of the lateral and longitudinal directions, may help improve the stability of the lifting apparatus 100. For example, constraining the movement of the first intermediate tower section 300 so that all points/portions on the intermediate tower section 300 translate vertically in unison with each other may help prevent the first intermediate tower section 300 from tilting relative to the bottom tower section 200 when it is in a raised position, and optionally also while it is moving between raised and lowered positions. Providing similar constraints between the second intermediate tower section 400 and the first intermediate section 300, and between the top tower section 500 and the second intermediate tower section 400, may help inhibit tilting of the second intermediate section 400 and the top tower section 500 respectively. The combined effect of inhibiting the tilting of each vertically translatable tower section 300, 400 and 500 relative to the lower tower section within which the upper tower section translates may help increase the overall stability of the top tower section 500 when the tower assembly 102 is extended, and optionally as it is moving between the extended and retracted configurations and the top tower section 500 is moving between its lowered and raised positions.
The movement of the tower sections 300, 400 and 500 may be constrained using any suitable mechanism. Optionally, for example, the bottom tower section may include a bottom track that extends vertically and is supported by the first and second bottom sidewalls 202a and 202b. The bottom track may engage and support any other tower section that is coupled to the bottom tower section, such as the first intermediate tower section 300 in the example illustrated. The track may guide the movement of the first intermediate tower section 300 relative to the bottom tower section to facilitate vertical translation and engagement with the bottom track may constrain tilting or other types of lateral movements.
Optionally, the bottom track may include at least one bottom guide member connected to each of the first and second bottom sidewalls 202a and 202b. In this configuration, the first carriage 350 may include at least one first carriage roller engaging each bottom guide member. Optionally, two or more of the first carriage rollers can be linked together to rotate in unison with each other. Linking the first carriage rollers to rotate in unison may help inhibit the first carriage 350 from moving vertically relative to only one of the bottom sidewalls 202a and 202b. In this configuration, the first carriage roller engaging the guide member on the first bottom sidewall 202a is inhibited from rotating relative to its guide member unless the first carriage roller engaging the guide member on the second bottom wall 202b also rotates relative to its guide member. This may help prevent one side (or end) of the first carriage 350 from slipping vertically relative to the other side (or end) of the first carriage, which may also help inhibit tilting of the first carriage 350 (and the rest of the first intermediate tower section 300).
The first section track and the second section track may include guide members that are analogous to those in the track in the bottom tower section. In this configuration, the second carriage 450 and the top carriage 550 may include analogous second carriage rollers and top carriage rollers to engage the first section track and the second section track, respectively. For example, the first section track may include at least one first section guide member connected to each of the first section first and second sidewalls 302a and 302b, and the second carriage 450 may include at least one second carriage roller engaging each first section guide member. Each of the second carriage rollers may be linked together to rotate in unison with each other. Similarly, the second section track may include at least one second section guide member connected to each of the second section first and second sidewalls 402a and 402b, and the top carriage 550 may include at least one top carriage roller engaging each second section guide member. Each of the top carriage rollers may be linked together to rotate in unison with each other.
Configuring the tower assembly 102 to inhibit the relative tilting of each individual tower section 300, 400 and 500 may also help enable the stability of the tower to remain generally constant regardless of its degree/amount of extension. For example, the stability of the tower assembly 102 when it is partially extended (
Referring to
Optionally, the first intermediate tower section 300 can be configured such that it is the first carriage 350 that engages and is constrained by the bottom track so that the first and second sides 352 and 352b of the first carriage will vertically translate substantially in unison with each other. This may help inhibit tilting of the first carriage 350, and therefore the rest of the first intermediate tower section 300 supported thereby, relative to the bottom tower section 200 in the lateral direction. The first carriage 350 may also be constrained in the longitudinal direction by the bottom track so that the first and second ends 354 and 356 will vertically translate substantially in unison with each other. This may help inhibit tilting of the first carriage 350, and therefore the rest of the first intermediate tower section 300 supported thereby, relative to the bottom tower section 200 in the longitudinal direction.
Similarly, the first intermediate section 300 may include a first section track to support and constrain the second intermediate tower section 400, and the second intermediate tower section 400 may include a second section track to support and constrain the top tower section 500.
In such a configuration, the second carriage 450 may be supported by and vertically translatable along the first section track and may be constrained by the first section track so that the first side 452a, second side 452b, first end 454 and second end 456 of the second carriage 450 will vertically translate substantially in unison with each other. This may help inhibit tilting of the second intermediate tower section 400 relative to the first intermediate tower section 300 in both the longitudinal direction and in the lateral direction. Similarly, the top carriage 550 may be supported by the second section track and may be vertically translatable along the second section track. The top carriage 550 may be constrained by the second section track so that the first side 552a, second side 552b, first end 554 and second end 556 of the top carriage 550 will vertically translate substantially in unison with each other. This may help inhibit tilting of the top tower section 500 relative to the second intermediate tower section 400 in the longitudinal and lateral directions.
As noted herein, optionally, each carriage 350, 450 and 550 may be provided with one or more rollers 363 for engaging an associated track. For example, the first carriage 350 may include one or more rollers to engage the bottom track. The rollers may help guide the first carriage 350 along the bottom track and may help facilitate vertical motion while helping to constrain tilting.
In the illustrated example the bottom track, first section track and second section track have generally the same configuration. The configuration of the bottom track, and its engagement with the first carriage 350 is explained in further detail herein, and the first section track and the second section track and the second carriage 450 and the top carriage 550 have analogous features and function in substantially the same manner. In the illustrated example the top tower section 500 does not include a track or guide members as it does not need to support any additional tower sections.
In the illustrated example, to engage the racks 260 in the bottom tower section 200, the rollers on the first carriage 350 are provided in the form of pinions 364 that have teeth configured to mesh with the teeth on the racks 260. Referring to
In the illustrated example, the pinions 364 located at the front end 354 of the first carriage 350 are both affixed to a common front shaft 366 so that they will rotate in unison with each other. Similarly, the pinions 364 at the back end 356 of the first carriage 350 are both affixed to a common rear shaft 368 so that they rotate in unison with each other. The first carriage 350 is also provided with a longitudinal connector member in the form of a shaft 370 that extends between, and is coupled to, the front and rear shafts 366 and 368. The longitudinal shaft 370 links the front and rear shafts 366 and 368 so that they rotate in unison with each other. The longitudinal shaft 370 is connected to the front shaft 366 via a front gear box 371, and the rear shaft 368 via a rear gear box 372. The front and rear gear boxes 371 and 372 are configured to so that rotation of the longitudinal shaft 370 in a first direction, illustrated by arrow 374, causes equal, corresponding rotation of all four pinions in opposite directions, shown by arrows 376a and 376b.
With the front and rear shafts 366 and 368 connected by the longitudinal shaft 370, all of the pinions 364 on the first carriage 350 are linked to rotate in unison with each other. In this configuration, each corner of the first carriage 350 will be held in a fixed position relative to the other corners as the first carriage 350 translates along the racks 260, and engagement between the teeth on the pinions 364 and the teeth on the racks 260 will support the weight of the first intermediate tower section 300 and all the components above the first intermediate tower section 300. Alternatively, instead of a longitudinal shaft 370, the front and rear shafts 366 and 368 may be linked by another suitable mechanism that limits relative rotation between the front and rear shafts 366 and 368, including, for example, gear trains, chains and belts.
In the example illustrated, external forces urging the first carriage 350 to tilt (for example a lateral load exerted on the first intermediate tower section 300) will be resisted by engagement between the teeth of the pinions 364 and the teeth of the racks 260. For example, when the pinion teeth are meshed with the rack teeth, vertical translation of the pinions 364 relative to the racks 260 is restricted in both the up and down directions by adjacent rack teeth; relative movement is only possible by rotation of the pinions. Since any one of the pinions can only rotate if all the pinions rotate, upward forces tending to lift only the first side 352a of the first carriage 350, as illustrated using arrow 378a, will be resisted by the engagement between the pinions 364 on the first side 352a and the racks 260 on the first bottom side wall 202a. The pinions 364 on the first side 352a cannot rotate, since the pinions on the second side 352b are, during tilting, preventing from rotating in a complimentary direction as would be necessary for vertically translating the entire carriage. In fact, during tilting, the second side 352b will generally be subject to corresponding forces urging the second side 352b of the first carriage downward, shown using arrow 378b. Tilting the second side downward would require reverse rotation of rollers on the second side relative to those on the upwardly urged first side. Since the rollers can only rotate in unison, the downward force on the second side is resisted by the engagement between the pinions 364 on the second side 352b and the racks 260 on the second bottom sidewall 202b. With both the upward and downward forces 378a and 278b resisted, neither side of the carriage can move vertically relative to the other side, and so the first carriage 350 will resist tilting and may remain substantially horizontal. A similar result will be achieved if the first carriage 350 is subjected to an external force acting in the longitudinal direction, or forces with components acting in both the lateral and longitudinal directions.
The second carriage 450, top carriage 550, first section track and second section track include similar features identified by like reference characters incremented accordingly, and are connected in an analogous manner.
Optionally, at least a portion of each track, including, for example the guide members can be coupled to and supported by the bracing members on the tower sections. This may help provide a strong, stable support for the guide members, and may help support the weight of components that are being supported by the guide members. In the illustrated example each rack 260 is coupled to a corresponding one of the uprights 262 and extends along substantially the entire height 218 of the first and second sidewalls 202a and 202b.
Stabilizing the tower sections via the interaction between the tracks and carriages may allow the tower sections to have very little vertical overlap with each other when in the extended position, without materially reducing the stiffness and/or stability of the tower assembly 102. This is in contrast to known telescoping boom assemblies, for example, in which a relatively larger amount of overlap between sections when extended is required to provide the necessary strength and stability. Referring to
The lifting apparatus 100 may be provided with any suitable type of elevating assembly that is operable to raise and lower the top tower section, while accommodating the engagement between the carriages and racks described herein. The elevating apparatus may include a lift actuator, and optionally, the lift actuator may be an electric actuator, such as, for example, an electric motor. Optionally, the electric actuator may be the only lift actuator provided, and the elevating assembly may be free from hydraulic components (such as reservoirs, cylinders and hoses). Providing the lifting apparatus with an all-electric elevating apparatus may eliminate the need to handle hydraulic fluid and may eliminate the risks of spilling or leaking hydraulic fluid. This may be advantageous if the lifting apparatus is used inside buildings and in other sensitive environments in which leaking or spilling hydraulic fluid is undesirable.
Optionally, the elevating assembly may be configured to act upon each tower section individually, or alternatively, may be configured to elevate two or more of the tower sections simultaneously. Elevating two or more tower sections simultaneously may help facilitate a relatively smoother extension of the tower assembly, as opposed to extending one tower section in its entirely, and bringing it to a stop, before elevating the next tower section.
Optionally, the elevating assembly may be a self-contained apparatus that is operable to elevate the tower sections without directly engaging other operating components of the tower, such as the rollers and guide members. Alternatively, the elevating apparatus may utilize the rollers and guide members to help raise and lower the tower sections, as well as helping to stabilize the tower sections. For example, the lift actuator may be configured to drive some or all of the rollers in a tower section so that the tower section can climb the guide members in an underlying, supporting tower section. Optionally, the rollers in two or more tower sections may be linked so that they are all driven in unison and in the same direction by the lift actuator. Optionally, in addition to being driven in the same direction, the rollers the two or more tower sections may also be driven at substantially the same speed, so that the two or more tower sections are raised at substantially the same rate.
Referring to
The electric motor 128 has an output shaft 130 and a drive sprocket 132 rotatable with the drive shaft 130. A drive chain 134a extends from the drive sprocket 132 to an input sprocket 136 that is provided on the first carriage 350. The input sprocket 136 (
Referring to
Providing a relatively high gear ratio may also help facilitate configuring the elevating assembly as generally self-braking, as the rotational force that is required to drive the worm gear in reverse, via the spur gear, is relatively high. This mechanical disadvantage faced by the spur gear when trying to drive the worm gear and the corresponding resistance to forcing the pinions 364 to rotate in a second direction to lower the first carriage 350 along the racks 260, about 1:30 in the illustrated example, may enable the first carriage 350 to resist moving downwardly under its own weight, and/or when subjected to vertical loading.
To lower the first carriage 350, the electric motor 128 can be driven in reverse, thereby driving the worm gear, spur gear and longitudinal shaft 370 in reverse and causing the pinions 364 to climb down the racks 260. To control the speed at which the first carriage 350 climbs the racks 260, the speed of the electric motor may be varied and/or a transmission module may be used.
Referring to
In the illustrated example, the drive chains 134a-c are all linked together and are driven in unison by the electric motor 128. In this configuration, all of the carriages 350, 450 and 550 are driven upwards or downwards at the same time, and in the example illustrated, at substantially the same rate.
While illustrated using a single motor 128 and connecting chains, in other examples each tower section may be provided with a separate motor (for example an electric servo motor), and extension of the tower assembly 102 may be controlled by operating the plurality of motors together.
Referring to
When the tower assembly 102 is extended (
Providing covers 284a, 284b, 384a, 384b, 484a and 484b that can be deployed to cover the upper portions 228, 231, 328, 331, 428 and 431 may help seal/enclose the interior of the tower assembly 102 when the tower assembly 102 is being extended and retracted, and when it is fully extended. Enclosing the bottom tower section 200, and some or all of the intermediate tower section 200 and 300 if present, may help prevent objects from falling into the interior of the tower assembly 102, being caught between adjacent tower sections as the tower assembly 102 is retracted or otherwise interfering with the operation of the tower assembly 102. Optionally, the covers may be structural members with a desired tensile strength and/or stiffness. Providing structural cover members may help increase each tower section further resist inward and/or outward lateral deflection of its sidewalls, which may help increase the stiffness of the tower sections.
Optionally, the covers 284a, 284b, 384a, 384b, 484a and 484b may be moveably coupled to their respective tower sections 200, 300 and 400 and may be movable from a stowed position in which the covers 284a, 284b, 384a, 384b, 484a and 484b are generally clear of their respective open, upper portions, and a deployed position in which the covers 284a, 284b, 384a, 384b, 484a and 484b generally covers their respective open upper portion.
Optionally, the cover on one tower section may be directly or indirectly coupled to an adjacent, higher tower section so that raising the adjacent higher tower section automatically moves the cover on the lower tower section toward its deployed position. For example, covers may be automatically deployed as tower assembly 102 is being extended so that open, upper portions 228, 231, 328, 331, 428 and 431 in the front and rear faces of each tower section are not left exposed because they are incrementally covered as the tower extends. When tower assembly 102 reaches its maximum extension, the covers may be fully deployed to cover substantially the entirety of the upper portions 228, 231, 328, 331, 428 and 431. When tower assembly 102 is only partially extended (
For example, in the illustrated example, the bottom covers 284a and 284b are coupled to the first intermediate tower section 300, which translates vertically when the tower is extended. As the first intermediate section 300 is raised relative to the bottom tower section 200 it automatically pulls the bottom covers 284a and 284b toward their deployed positions. Similarly, the first intermediate tower section covers 384a and 384b are coupled to the second intermediate section 400 and the second intermediate tower section covers 484a and 484b are coupled to the top tower section 500.
Referring to
In the illustrated example, the first and second bottom front cover panels 285a and 286a are vertically translatable relative to each other and to the first and second bottom sidewalls 202a and 202b between respective a lowered position (
The first and second front cover 285a and 286a panels are sized so that the combined heights of the first and second front cover panels 285a and 286a is generally equal to the height of the open, upper portion 228 in the front face. In the illustrated example, the first and second front cover panels 285a and 286a are generally the same height as each other, and as the bottom front wall 226 (each approximately a third of the height of the bottom side walls 202a and 202b). When tower assembly 102 is only partially raised, the first and second front panels 285a and 286a may vertically overlap each other and/or the bottom front wall 226 (
In the illustrated example, the bottom rear cover 284b is generally identical to the bottom front cover 284a, and includes corresponding first and second rear cover panels 285b and 286b that can slide in respective channels provided at the rear edges of the first and second bottom sidewalls 202a and 202b in an analogous manner. The first and second intermediate tower sections 300 and 400 also have similar front and rear covers, with vertically translating cover panels, which are identified by like reference characters, incremented accordingly.
Referring to
Optionally, the lifting apparatus 100 may be configured as a slab machine designed to roll across generally smooth surfaces, such as floors and paved surfaces, and to fit through a standard internal/interior doorway. Configuring the apparatus 100 to fit through a standard doorway may help facilitate use of the lifting apparatus 100 inside buildings and to be moved from one room to another room without requiring significant modification to the building.
Referring to
In the example illustrated, the tower outer width 212 is about 81 cm which is about equal to the overall apparatus width 140, and the bottom sidewall height 218 may be at least 80% of the overall apparatus retracted height 142, and in the illustrated example is about 195 cm which is about 95% of the apparatus retracted height 142. This may allow the bottom tower section 200 to extend substantially the overall apparatus width 140, and a majority of the overall apparatus retracted height 142 of the lifting apparatus 100. Providing a relatively wide bottom tower section 200, and subsequent tower sections mounted thereto, may help stiffen the tower assembly 102. Providing a relatively tall bottom tower section 200 may help facilitate extending the work platform 104 to a relatively higher height, as compared to a lifting apparatus with a relatively shorter bottom tower section.
Referring to
Optionally, one or both of the wheel assemblies can be provided with steerable wheels. In the illustrated example, the first wheel assembly 146 includes two steerable wheels 150. Each wheel 150 is rotatable about a rotation axis 152 and can be steered by pivoting about respective pivot axes 154. In the illustrated example, the first wheel assembly 146 includes electric steering motors 156 to steer the wheels 150, and an electric propulsion motor 158 to drive rotation of the wheels 150 (see also
The second wheel assembly 148 also includes two wheels 160 which are rotatable about a horizontal rotation axis 162. In the illustrated example, the wheels 160 are not steerable.
Referring to
Positioning the bottom face 293 of the bottom tower section at a relatively low elevation may help facilitate positioning other components of the lifting apparatus 100 at relatively low elevations. For example, referring to
Referring to
Optionally, the first and second wheel assemblies 146 and 148 may be adjustable to raise and lower the tower assembly 102 relative to the surface (i.e. to change the distance 178 between the bottom face 293 and the surface). In the illustrated example, each wheel assembly 146 and 148 includes a mounting plate 180 for attaching to the bottom tower section 200 (
The mounting plates 180 can be moved to a variety of different positions. In the example illustrate, three different positions for the mounting plates 180 are shown in
For example, the first and second wheel assemblies can be adjusted to support the tower assembly at a travelling height 178 when the tower assembly is retracted (
The wheel assemblies 146 and 148 can then be lowered to support the tower assembly 102 at a lower, extension height 182 when the tower assembly 102 is at least partially extended (
Optionally, the wheel assemblies 146 and 148 may also be adjustable to lower the tower assembly 102 to a lowered, transport position (
For example, to help secure the lifting apparatus 100 to a truck bed during transport the lifting apparatus 100 may be tied down or secured to the bed using tie downs, including for example, straps or chains. Such tie downs can exert significant downward forces on the lifting apparatus 100. By lowering the bottom face 293 to a position where it rests on the truck bed, at least a portion of these tie down forces can be carried by the bottom tower section, instead of via the wheel assemblies 146 and 148. This may reduce the wear on the bearings and other load bearing components of the wheel assemblies 146 and 148.
While illustrated as being attached to the front and rear faces of the bottom tower section, the first and second wheel assemblies may alternatively be connected to the first and second bottom sidewalls.
While the lifting apparatus 100 includes two intermediate tower sections between the bottom and top tower sections (for a total of four tower sections), in other examples a lifting apparatus may optionally include only one intermediate tower section, more than two intermediate tower sections or no intermediate tower section (i.e. the top tower section may be directly connected to the bottom tower section).
Optionally one or more portions of the top tower section may be integrated with the work platform. For example, the top carriage may be integrated with the work platform and may be position generally adjacent the lower side of the work surface.
Referring to
In this example, the guide members are provided in the form of generally vertically extending chains 1260 that are attached to the supporting tower section, for example to a bottom sidewall 1202a. The chains 1260 may be any suitable type of chain, and in the illustrated example are roller chains. The chains 1260 are anchored to the bottom sidewall 1202a at their top ends, and may also be anchored at their bottom ends and at one or more locations along their length. Like the racks 260, the chains 1260 extend substantially the entire height of the tower section sidewall 1202a.
In this example, the carriage 1350 is provided with rollers 1363 in the form of sprockets 1364 that are configured to engage the chains 1260. The sprockets 1364 at the front end 1354 of the carriage 1350 are affixed to a common front shaft 1366 so that they rotate in unison, and cannot rotate relative to each other. Similarly, the sprockets 1364 at the rear end 1356 of the carriage 1350 are affixed to a common rear 1368 shaft to rotate in unison with each other.
To help the front and rear shafts 1366 and 1368 to rotate in unison, so that one cannot rotate relative to the other, in the illustrated example the carriage 1350 utilizes a longitudinal connector in the form of a transfer chain assembly 1371 to synchronize rotation of the front and rear shafts 1366 and 1368, instead of the longitudinal shaft 370.
Referring to
Referring to
Referring to
In the illustrated example the bottom tower section 5200 includes a first bottom sidewall 5202a and an opposing second bottom sidewall 5202b (
Referring to
Referring also to
Referring to
In the illustrated example, the pinions 5364 located at the front end 5354 of the first carriage 5350 are both affixed to a common front shaft 5366 so that they will rotate in unison with each other. Similarly, the pinions 5364 at the back end 5356 of the first carriage 5350 are both affixed to a common rear shaft 5368 so that they rotate in unison with each other. The first carriage 5350 is also provided with a longitudinal connector member in the form of a shaft 5370 that extends between, and is coupled to, the front and rear shafts 5366 and 5368. The longitudinal shaft 5370 links the front and rear shafts 5366 and 5368 so that they rotate in unison with each other. The longitudinal shaft 5370 is connected to the front shaft 5366 via a front gear box 5371, and the rear shaft 5368 via a rear gear box 5372. The front and rear gear boxes 5371 and 5372 are configured so that rotation of the longitudinal shaft 5370 in a first direction, represented by arrow 5374, causes equal, corresponding rotation of all four pinions in opposite directions. In the example illustrated, upon rotation of the synchronizing shaft 5370 in the direction of arrow 5374, the two pinions 5364 attached to the front shaft 5366 rotate in a clockwise direction (arrow 5376a—as viewed from side 5352a), and the two pinions 5364 attached to the rear shaft 5368 rotate in the counterclockwise direction (arrow 5376b—as viewed from side 5352a), shown by arrows 5376a and 5376b.
With the front and rear shafts 5366 and 5368 connected by the longitudinal shaft 5370, all of the pinions 5364 on the first carriage 5350 are linked to rotate in unison with each other. In this configuration, each corner of the first carriage 5350 will be held in a fixed position relative to the other corners as the first carriage 5350 translates along the racks 5260, and engagement between the teeth on the pinions 5364 and the teeth on the racks 5260 will support the weight of the first intermediate tower section 5300 and all the components above the first intermediate tower section 5300.
If external forces urging the first carriage 5350 to tilt are applied to the first intermediate tower section 5300 (for example a lateral load exerted on the first intermediate tower section), such forces will be resisted by engagement between the teeth of the pinions 5364 and the teeth of the racks 5260. A similar result will be achieved if the first carriage 5350 is subjected to an external force acting in the longitudinal direction or forces with components acting in both the lateral and longitudinal directions.
The second carriage 5450 and top carriage 5550 include similar features as the first carriage, identified by like reference characters indexed accordingly (see
Referring to
In the illustrated example, the elevating assembly includes a lift actuator that includes three electric motors 5128a, 5128b and 5128c. In this example, instead of a single motor 128 in the bottom tower section 200 and drive chains extending between the carriages 350, 450 and 550 (as provided in the mobile lifting apparatus 100), each carriage 5350, 5450 and 5550 is provided with its own electric motor. The motors 5128a, 5128b and 5128c can be controlled using any suitable controller, and may be configured so that they are operable in unison (so that all of the carriages 5350, 5450 and 5550 are moved in unison) or so that one or more of the motors 5128a, 5128b and 5128c may be operated independently of the other motors. Providing individually operable motors may allow a user to move a particular carriage, such as the first intermediate carriage 5350 or the top carriage 5550, without having to move the other carriages. This may help increase the versatility of the mobile lifting apparatus 5100 by helping to facilitate independent positioning of each tower section, and may eliminate the need to lift the weight of the lower tower sections if only the top tower section need be extended. Alternatively, configuring the motors to be controlled in unison may allow the tower assembly 5102 to extend and retract in a generally uniform manner.
Referring to
The motor 5128a (and optionally motors 5128b and 5128c) can be provided with a braking mechanism that can be activated to impede and/or prevent rotation of the shaft 5388. In the illustrated configuration, preventing rotation of the motor shaft 5388 can also prevent rotation of the shafts 5366, 5368, 5370 and pinions 5364, thereby holding the first carriage 5350 in a fixed position relative to the racks 5260. This may allow the motor braking mechanism to be used as a carriage braking mechanism to help prevent unwanted movement of the first carriage 5350 (and analogously of the other carriages 5450 and 5550). Alternatively, or in addition to a braking mechanism associated with the motor, one or more of the gearbox 5386, shafts 5366, 5368 and 5370, gearboxes 5371 and 5372 or other suitable component may be provided with a breaking mechanism.
The motor 5128a can be controlled using any suitable type of controller apparatus. Optionally, the controller apparatus may be a single controller that is connected to each of the motors 5128a, 5128b and 5128c using wires or other suitable connectors. Alternatively, the controller apparatus may include more than one controller. For example, the controller apparatus may include one controller per motor. Referring to
Optionally, the controllers 5390, 5490 and 5590 can be communicably linked together so that they can operate in concert which can help provide coordinated movement of the carriages 5350, 5450 and 5550 in a desired manner, such as, for example so that the carriages 5350, 5450 and 5550 can move in unison. The controllers 5390, 5490 and 5590 can be linked using any suitable communication link, such as a wire and/or a wireless communication system.
Referring to
Referring to
Referring to
The recess 5394 is generally registered beneath the motor 5128b on the second carriage 5450 and is sized to receive at least a portion of the motor 5128b when the tower assembly 5102 is retracted. Similarly, the recess 5494 is generally registered above the motor 5128a and is sized to receive at least a portion of the motor 5128a when the tower assembly 5102 is retracted. In this configuration, when the second carriage 5450 approaches the first carriage 5350, portions of the motor 5128b that extend below the second carriage 5450 can be received within the recess 5394 so that the motor 5128b is partially nested within the first carriage 5350, and portions of the motor 5128a that extend above the first carriage 5350 are received within the recess 5494 so that the motor 5128a is partially nested within the second carriage 5450. This arrangement may help facilitate the stacking of the carriages 5350 and 5450 and provide a reduced height when stacked. In the illustrated example, the recesses 5394 and 5494 also receive portions of the cable track apparatus when the carriages 5350, 5450 and 5550 are stacked.
While illustrated as through-holes in the carriages 5350 and 5450, the recesses 5394 and 5495 need not be configured as through holes. Instead, the recesses may be formed as cavities or chambers that are sized to accommodate portions of the motors 5128b and 5128a, but do not extend all the way through the carriages 5350 and 5450.
Referring to
Stacking the carriages 5350, 5450 and 5550 closely together in the vertical direction (for example as illustrated in
Alternatively, the carriages 5350, 5450 and 5550 need not be stacked on in contact each other or in close proximity when the tower assembly 5102 is retracted. Instead, the carriages 5350, 5450 and 5550 may be vertically spaced apart from each other when the tower assembly 5102 is retracted.
Optionally, some or all of the carriages can be provided with an alignment mechanism to help facilitate a desired alignment between a carriage and its respective track. For example, the alignment mechanism may help maintain a desired lateral spacing between the carriage and its track. This may help facilitate the desired engagement between the rollers on the carriage and the track, which may help inhibit tilting of the carriage relative to the track. For example, the use of an alignment mechanism may help keep the teeth on the pinions sufficiently engaged with the teeth on the racks. This may help reduce backlash between the racks and pinions and may help inhibit tilting or shifting of the carriages relative to the racks.
The alignment mechanism may be of any suitable configuration that can help facilitate alignment of the carriage relative to its track, preferably without unduly inhibiting or restricting the translation of the carriage along the track when the tower is raised or lowered. Optionally, the alignment mechanism can include one or more alignment tracks, provided on one of the carriages or the tower sections, and one or more followers provided on the other one of the carriages or the tower sections to engage the alignment tracks. The followers may be any suitable members, including, for example, sliders, pads, rollers, bushings, wheels, pinions or other members that can engage the alignment tracks.
Optionally, the alignment mechanism may be provided on only some of the tower sections and the carriages that engage the tower sections, such as, for example, only on the bottom tower section or only on the top tower section. Alternatively, the alignment mechanism may be provided on all of the tower sections and carriages in the mobile lifting apparatus.
An alignment mechanism may be used in combination with some or all of the features of the mobile lifting apparatuses 100 and 5100 described herein.
Referring to
In the illustrated example, the tower section 6200 includes a rack 6260 for engaging a corresponding pinion on the carriage 6350. The mobile lifting apparatus also includes an example of an alignment mechanism 6600 to help facilitate alignment of the carriage 6350 with the tower section 6200. In the illustrated example, the alignment mechanism 6600 includes an alignment track in the form of a rail 6602 provided on tower section 6200, and a complimentary follower in the form of roller 6604. The roller 6604 is configured to engage the rail 6602, and to roll along the length of the rail 6602 as the carriage 6350 translates relative to the tower section 6200. The rail 6602 extends parallel to the rack 6260, and in the illustrated example is integrally formed with the rack 6260.
Referring also to
Optionally, in addition to, or as an alternative to resisting lateral movement of the carriage 6350, the alignment mechanism can be configured to inhibit movement of the carriage 6350 in at least one other direction (e.g. a longitudinal direction) relative to the tower section 6200. For example, the alignment mechanism may be configured to inhibit forward movement of the carriage, rearward movement of the carriage or both forward and rearward movement of the carriage relative to the tower section 6200. Inhibiting movement of the carriage 6350 relative to the tower section 6200 in at least two directions may help increase the stability of the mobile lifting apparatus, and/or may help keep the carriage 6350 in its desired position relative to the tower section 6200 (e.g. laterally and longitudinally centered relative to the tower section 6200).
Referring to
In the illustrated example, the rail 6602 includes a third abutment surface 6610c that is positioned to abut an outer, third roller abutment surface 6608c. Engagement between abutment surfaces 6608c and 6610c may also help inhibit rearward movement of the carriage 6350 relative to the tower section 6200.
In other examples, the rail engagement member may be provided as a groove or slot, and the roller engagement member may include a tongue or other suitable protrusion that can be received within the groove or slot.
While illustrated as being integrally formed with each other in this example, alternatively, the rail and rack need not be integrally formed and instead may be provided as separate members.
Referring to
In the illustrated example, the tower section 7200 includes a rack 7260 for engaging a corresponding pinion on the carriage 7350. The mobile lifting apparatus also includes an example of an alignment mechanism 7600 to help facilitate alignment of the carriage 7350 with the tower section 7200. In the illustrated example, the alignment mechanism 7600 includes an alignment track in the form of a rail 7602 provided on tower section 7200, and a complimentary follower in the form of a pair of rollers 7604. The rollers 7604 are spaced apart from each other in the vertical direction (i.e. a direction parallel to the rail) and configured to engage the rail 7602 at two vertically spaced apart locations. This may help inhibit tilting of the carriage 7350 relative to the tower section 7200. The rollers 7604 are configured to roll along the length of the rail 7602 as the carriage 7350 translates relative to the tower section 7200. The rail 7602 extends parallel to the rack 7260, and in the illustrated example is integrally formed with the rack 7260.
Referring also to
In this configuration, engagement between the rollers 7604 and the rail 7602 can inhibit movement of the carriage 7350 toward the rail 7602 (to the left as illustrated in
Referring to
What has been described above has been intended to be illustrative of the invention and non-limiting and it will be understood by persons skilled in the art that other variants and modifications may be made without departing from the scope of the invention as defined in the claims appended hereto. The scope of the claims should not be limited by the preferred examples and examples, but should be given the broadest interpretation consistent with the description as a whole.
| Number | Date | Country | |
|---|---|---|---|
| 61913629 | Dec 2013 | US | |
| 62059011 | Oct 2014 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/CA2014/051188 | Dec 2014 | US |
| Child | 15177556 | US |
