(19)
(11)EP 2 387 526 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
14.08.2019 Bulletin 2019/33

(21)Application number: 10732186.1

(22)Date of filing:  15.01.2010
(51)International Patent Classification (IPC): 
G05D 1/02(2006.01)
B62D 5/04(2006.01)
E04H 6/00(2006.01)
E04H 6/24(2006.01)
E04H 6/36(2006.01)
B60K 17/30(2006.01)
B62D 7/02(2006.01)
E04H 6/18(2006.01)
E04H 6/30(2006.01)
(86)International application number:
PCT/US2010/021284
(87)International publication number:
WO 2010/083473 (22.07.2010 Gazette  2010/29)

(54)

OMNIDIRECTIONAL DRIVE AND STEERING UNIT

OMNIDIREKTIONALER ANTRIEB UND LENKEINHEIT DAFÜR

ENTRAÎNEMENT OMNIDIRECTIONNEL ET UNITÉ DE DIRECTION


(84)Designated Contracting States:
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO SE SI SK SM TR

(30)Priority: 04.11.2009 US 258006 P
17.01.2009 US 145543 P
03.10.2009 US 248448 P

(43)Date of publication of application:
23.11.2011 Bulletin 2011/47

(73)Proprietor: Boomerang Systems, Inc.
Morristown, New Jersey 07960 (US)

(72)Inventors:
  • SWASEY, Merin
    Morristown, NJ 07960 (US)
  • CHECKETTS, Stanley, J.
    Morristown, NJ 07960 (US)

(74)Representative: Carpintero Lopez, Francisco et al
Herrero & Asociados, S.L. Cedaceros 1
28014 Madrid
28014 Madrid (ES)


(56)References cited: : 
GB-A- 2 271 092
JP-A- 2003 156 129
US-A- 4 664 213
JP-A- 2002 061 736
JP-A- 2003 194 157
US-A- 4 733 737
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    CROSS-REFERENCE TO RELATED APPLICATIONS



    [0001] This application claims the benefit of U.S. Application 61/145,543, filed January 17, 2009, U.S. Application 61/248,448, filed October 3, 2009, and U.S. Application 61/258,006, filed November 4, 2009.

    FIELD OF THE INVENTION



    [0002] The present invention relates to a wheel drive and steering unit for, in one embodiment, automatic guided vehicles (AGVs) and other semi-automatic or manually controlled vehicles. More particularly, the present invention relates to a compact and low profile drive and steering unit that has a unique ability to fully rotate a vehicle around its central vertical axis, and to drive or move a vehicle in any direction without altering the orientation of the vehicle.

    BACKGROUND OF THE INVENTION



    [0003] Conventional AGVs rely upon gear units that house separate drive and steering components that are adjacent to a load carried by a vehicle. For example, conventional AGVs employ two turnable and two non-turnable wheels, much like a forklift, where the drive and steering mechanisms are adjacent to the load. That design simplifies the mechanical components of the system, but limits the amount of the load a vehicle can carry and the maneuverability of the vehicle. The load is limited because the placement of the drive and steering components adjacent to the load increases the top-heaviness of the vehicle. Maneuverability is constrained because only two wheels are capable of turning.

    [0004] In addition, existing omnidirectional drive and steering units are relatively delicate in construction, large in design, and provide minimal power for steering, drive, and load bearing functions relative to the overall size of the unit.

    [0005] The document US 4,733,737 A discloses according to the preamble of claim 1 a driveable, steerable platform for industrial, domestic, entertainment and related uses. A frame member travels on a plurality of wheels which can be turned 360° to steer the platform in a desired direction. Separate endless drive means in the form of gear-driven concentric shafts drive and steer the wheels. The platform travels substantially parallel to the terrain traversed. The entire platform may be housed in a hollow sphere to cause the sphere to selectively roll, providing the platform the ability to move about on radically uneven terrain including the ability to climb steps of height equal to approximately one-half the sphere's diameter. The wheels engage the inner surface of the rolling sphere to drive and steer the rolling sphere.

    SUMMARY OF THE INVENTION



    [0006] The present invention discloses, in one embodiment, a compact wheel drive and steering system that is preferably placed under a load, or in one example a vehicle, rather than adjacent thereto, and that is capable of rotating a vehicle to any degree around its central vertical axis, and of moving a vehicle in any direction without altering its orientation or that of a load.

    [0007] The placement of the system under a vehicle increases the load capability, and the omnidirectional nature of the drive and steering system improves maneuverability and reduces the space or area necessary for vehicle operation. For example, an AGV equipped with one or more omnidirectional steering and drive units of the present invention working in a coordinated fashion, operating in an automated parking facility, can slide under an automobile because of the placement and compactness of the drive and steering units, lift the automobile and turn around without using a turntable or making a U-turn in an arc, travel for a distance and deposit the automobile in a storage space or aisle that is normal to the direction of the vehicle without changing the orientation of the vehicle or using floor space for the arc required for a vehicle turning radius.

    [0008] The omnidirectional drive and steering system of the present disclosure provides an AGV or other vehicle with multidirectional travel capability, the ability to turn 360° so that vehicles can be driven forward into the structure and also driven forward when exiting the structure, and a more efficient mode of maneuvering automobiles to and from storage within the system which can increase system efficiency and significantly decrease costs associated with storage system footprint, construction and maintenance.

    [0009] One aspect of the invention is to provide a drive and steering unit that is very low profile and compact, and that is capable of transporting heavy loads. Another aspect is to provide a drive and steering unit that does not require changing gears to reverse directions. Another aspect is to provide a device where the drive and steering unit can be placed directly below the load providing a 360° turning capability within the diameter of the footprint of the load. Another aspect is to provide a drive function that operates independent of the steering function within a low profile, compact housing.

    BRIEF DESCRIPTION OF THE DRAWINGS



    [0010] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate certain embodiments of an omnidirectional drive and steering unit and together with the description, serve to explain certain aspects of the principles of this application.

    FIG. 1 is an exploded view of an omnidirectional drive and steering unit of the present invention.

    FIG. 2 is an isolated view of one aspect of an omnidirectional drive and steering unit attached to drive and steering motors.

    FIG. 3 is an exploded view of one aspect of an upper case assembly of the invention.

    FIG. 4 is a flow diagram of the assembly of one embodiment of one aspect of the omnidirectional drive and steering unit of the invention.

    FIG. 5 is a flow diagram of the assembly of one embodiment of an upper case assembly of the invention.

    FIG. 6 is an exploded view of one embodiment of a wheel pinion gear and wheel housing assembly of the invention.

    FIG. 7 is a flow diagram of the assembly of one embodiment of a wheel and pinion gear assembly of the invention.

    FIG. 8 is a flow diagram of the assembly of one embodiment of a wheel housing assembly of the invention.

    FIG. 9 is an exploded view of one embodiment of a worm gear assembly of the invention.

    FIG. 10 is an exploded view of one embodiment of a lower case assembly of the invention.

    FIGS. 11A and 11B are a flow diagram of the assembly of one embodiment of a case assembly of the invention.

    FIG. 12 is a top view of the omnidirectional drive and steering unit, constructed in accordance with the present invention;

    FIG. 13 is a cross-section taken along line 13-13 of FIG. 12.

    FIG. 14 is a perspective view taken from the bottom of one embodiment of certain sections of the omnidirectional drive and steering unit of the invention.

    FIG. 15 is a perspective view taken from the side of one embodiment of certain sections of the omnidirectional drive and steering unit of the invention.

    FIG. 16 is a perspective view taken from the bottom of one embodiment of certain sections of the omnidirectional drive and steering unit of the invention.

    FIG. 17 is a bottom view of one embodiment of an AGV including a pair of omnidirectional drive and steering units.


    DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS



    [0011] This disclosure describes the best mode or modes of practicing the invention as presently contemplated. This description is not intended to be understood in a limiting sense, but provides an example of the invention presented solely for illustrative purposes by reference to the accompanying drawings to advise one of ordinary skill in the art of the advantages and construction of the invention. In the various views of the drawings, like reference characters designate like or similar parts.

    [0012] Figure 1 is an exploded view of one embodiment of an omnidirectional drive and steering unit 10 (hereinafter referred to as unit 10) generally comprising an upper case assembly 12, a lower case assembly 16, a wheel housing assembly 14 enclosing a wheel 54, and a drive assembly 18. One embodiment of a method of assembly of each generally-referenced region is further illustrated in the figures that follow, where Figure 3 illustrates one embodiment of an assembly of the upper case assembly 12, Figure 10 illustrates one embodiment of an assembly of the lower case assembly 16, Figure 6 illustrates one embodiment of an assembly of the wheel housing assembly 14, and Figure 9 illustrates one embodiment of an assembly of the drive assembly 18. As will be described in more detail below, the upper and lower case assemblies 12, 16 are preferably fixed relative to an AGV (Figure 17), for example, to which the unit 10 is attached. The drive assembly 18 is adapted for rotating the wheel 54 either forward or backward without switching drive gears, while the wheel housing assembly 14 is rotatably steered within the upper and lower case assemblies 12, 16 through engagement with a steering gear 90. As will be further described below, the wheel 54 can be driven and steered or turned independently or simultaneously as desired.

    [0013] Figure 2 illustrates one embodiment of a bottom view of the unit 10 showing the steering gear 90 coupled to a steering motor 200 via a belt 210, and a drive motor 250 coupled to a drive shaft 102 of the drive assembly 18 (see Figure 1) through a coupling 260. While the embodiment of Figure 2 shows the steering gear 90 being driven by a belt 210, it will be appreciated that the steering gear 90 could be driven by other means, such as by another gear coming off of the steering motor 200, or through a direct connection with the steering motor 200. Having the steering motor 200 laterally spaced from the steering gear 90 and the rest of the unit 10 aids in maintaining a low profile for the unit 10. The steering motor 200 and drive motor 250 are also preferably independent from each other so that the unit 10 can be independently driven and steered. Each motor 200, 250 is preferably associated with a control system 220, 270 that is preferably associated with a processor (not shown) that guides the movement and direction of the unit 10 and of an AGV or the like (Figure 17). If multiple units 10 are employed in an AGV or the like (Figure 17), then each unit 10 would preferably have its own steering and drive motor assemblies so that each unit 10 can be independently driven and steered relative to the other units 10.

    [0014] Various methods of assembly of each region will now be described, it being understood that certain aspects of assembly are described and that other aspects and embodiments of assembly are contemplated. Furthermore, while certain methods of construction are described herein, it will be appreciated that such methods of assembly are not limited to the embodiments as shown, or the described order of assembly, but that various methods of assembly in various orders are contemplated.

    [0015] Figure 3 is an exploded view of the upper case assembly 12, worm gear 24, and bevel gear 26, and Figure 4 is a flow diagram illustrating one embodiment of assembling the same. In one embodiment, outside diameter contact bearing 30 is pressed into the bevel gear 26 and held in place by snap ring 32 after the shape of the snap ring is adjusted if necessary. The snap ring 32 fits within a snap ring groove (not shown) on the bevel gear 26. Dowel pins 34 are preferably inserted into the bevel gear 26 for alignment with the gear mounting ring 36 when the gear mounting ring 36 is pressed onto the bevel gear 26. The dowel pins 34 are preferably pressed flush to the surface of the gear mounting ring 36, and then the bevel gear 26 is attached to the gear mounting ring 36 by fasteners such as Allen head screws 38 for example. Of course, other types of fasteners may be used. Additional dowel pins 34 are used to align the worm gear 24 with the assembly of the bevel gear 26 and gear mounting ring 36, which are then secured to each other with fasteners such as machine screws 40 to form an assembly of the worm gear 24, bevel gear 26 and gear mounting ring 36. Top wheel support 76 (see Figure 1) is inserted into the assembly of the worm gear 24, gear mounting ring 36 and bevel gear 26 and aligned with such assembly with dowel pins.

    [0016] Figure 5 is a flow diagram illustrating the upper case assembly 12, where outside diameter contact bearing 30 is placed on the upper case 28 and pressed into position below the snap ring groove 83 and snap ring 84 (Figure 1). The shape of the snap ring 84 is adjusted as required and inserted into the snap ring groove 83 in the upper case 28. Gasket sealant or the like is preferably applied to the mating surfaces of the bearing cap 42 and top wheel support 76. The bearing cap 42 is then aligned with and secured to the top wheel support 76 with bearing cap mounting fasteners or screws 44. As illustrated in Figures 1 and 3, top cover 46 is secured to the upper case 28 with mounting fasteners or screws 48.

    [0017] Figure 6 is an exploded perspective of the drive wheel 54, pinion gear 56 and wheel housing components 14. The wheel drive shaft 58 is shown below the drive wheel 54 along with a long key 60 that engages a slot 55 in the drive wheel 54 and a short key 62 that engages a slot 57 in the pinion gear 56. Above the drive wheel 54 is a snap ring 64, laminated shim 66 and drive shaft bearing 68. On the other side of the drive wheel 54 is a laminated shim 66, drive shaft bearing 68, oil seal 70, pinion gear 56 and snap ring 64. To the left of the wheel drive shaft 58 in Figure 6 is lower wheel bearing housing 72, and to the right is an upper wheel bearing support 74 and the top wheel support 76 (see also Figure 1). The lower wheel bearing housing 72, upper wheel bearing support 74 and the top wheel support 76 are positioned by long dowel pins 78 and attached by fasteners such as, for example, machine screws 80. The top case outside diameter bearing 82 and the snap ring 84 are shown in alignment with the top wheel support 76.

    [0018] Figure 7 is one embodiment of a flow diagram of the assembly of the wheel and pinion gear assembly of Figure 6. The wheel drive shaft 58 is pressed into the drive wheel 54 along with the long key 60 in the keyway (not shown on the drive shaft) until the snap ring groove 59 on the distal end of the wheel drive shaft 58 passes beyond the outside of the drive wheel 54. The snap ring 64 is installed into the snap ring groove 59, the drive wheel 54 is pressed against the snap ring 64, and then laminated shim 66 is placed on the wheel drive shaft 58 on top of the snap ring 64. Another laminated shim 66 is placed on the wheel drive shaft 58 on the opposite side of the drive wheel 54, where the distance between the laminated shims 66 on either side of the drive wheel 54 is preferably approximately 3.125 inches. Other spacing is contemplated depending on the size of the drive wheel 54 and the environment, and some adjustment of the laminated shims 66 may be required. The drive shaft bearings 68 are positioned on the drive shaft 58 on either side of the drive wheel 54. The pinion gear 56 is placed on the wheel drive shaft 58 with a snap ring 64, although preferably not initially using the short key 62 to make corrections in the position of the pinion gear 56 by adjusting the laminated shims 66 on either side of the drive wheel 54. The pinion gear 56 can be removed from the wheel drive shaft 58 to install the oil seal 70 over the wheel drive shaft 58, and then the pinion gear 56 is re-seated on the drive shaft 58 with the short key 62 and snap ring 64. All above-mentioned parts are preferably lubricated at assembly as required.

    [0019] Figure 8 is one embodiment of a flow diagram discussing the wheel housing assembly 14 shown in Figure 6. Mating surfaces of the top wheel support 76 and upper wheel bearing support 74 are preferably coated with gasket sealant and then the top wheel support 76 is positioned over the upper wheel bearing support 74 using alignment dowel pins 78. The wheel and pinion gear assembly described in Figures 6 and 7 is placed into the upper wheel bearing support 74 and the lower wheel bearing housing 72 is then pressed onto the dowel pins 78 extending from the upper wheel bearing support 74. Thereafter, the top wheel support 76, upper wheel bearing support 74 and the lower wheel bearing housing 72 are secured by, for example, machine screws 80.

    [0020] Figure 9 is an exploded view of one embodiment of the drive assembly 18 comprising a worm assembly 98 including a worm 100 and worm shaft 102 with tapered bearings 104, 106 and shaft seals 112, 114 at either end. While the worm 100 and worm shaft 102 are shown as a single machined part, it will be understood that other methods of manufacture and assembly are contemplated. In addition, while a drive assembly 18 based on a worm drive is shown and described, it will be appreciated that other drive systems will be operable. The worm assembly 98 is attached to the upper and lower cases 28, 86 through the use of worm seal mounting plates 108 and 110 that are secured to the upper and lower cases 28, 86 with threaded fasteners 116 and lock washers 118 or the like. Other methods of securing and fastening are contemplated.

    [0021] Figure 10 is an exploded view of one embodiment of the lower case assembly 16 (Figure 1) comprising the lower case 86, lower case seal 88 and the steering gear 90. The steering gear 90 is attached to the lower wheel bearing housing 72 (Figure 1) with fasteners 92, such as Allen head screws 92 for example, while other fasteners 94, such as machine screws 94 for example, are used to attach the lower case 86 to the upper case 28 (Figure 1). As also shown in Figures 1, 2 and 17, while the steering gear 90 is disposed outside of the lower case 86 for engagement with a steering motor 200 or the like (Figure 2), the steering gear 90 also engages the wheel assembly 14 through fixed engagement with the lower wheel bearing housing 72.

    [0022] Figures 11A and 11B describe one embodiment of an assembly of the upper and lower cases 28, 86 of the unit 10. It will be appreciated that while one non-limiting sequence of assembly is described in some detail, other methods of assembly will be contemplated. First, the lower case oil seal 88 is pressed into the lower case 86 (Figures 1, 10). The lower case 86 is then turned over on a work surface (not shown) for applying gasket sealant to the mating edges of both the upper case 28 and the lower case 86 and for lightly greasing the seal mating surface where lower wheel bearing housing 72 meets the lower case oil seal 88 (Figure 1). Placing the lower case assembly 16 onto upper case assembly 12 and pressing the lip of the lower case oil seal 88 in around the edge of the lower wheel bearing housing 72 ensures an even fit and adequate seal. Machine screws 94, for example, which join the upper case 28 to the lower case 86, are tightened by first tightening the screws in the rectangular area above the worm 100 (Figure 1) until they are snug and the gasket cement squeezes out, and the remaining screws are tightened to secure the lower case 86 to the upper case 28. The assembly of the upper and lower cases is turned over and it is determined where the pinion gear 56 is currently positioned relative to the bearing cap 42 and such location on the bearing cap 42 is marked. In accordance with one method, a series of punch marks in the bearing cap 42 roughly resembling an arrow shape are made using a hammer and center punch, for example, to mark the location directly over the pinion gear 56. Thereafter, the worm shaft seal 112 (Figure 9) is advanced slightly onto the worm seal mounting plate 108 with the open side of the seal 112 going in towards a stop machined into the worm seal opening in the plate 108. The worm shaft seal 112 and worm seal mounting plate 108 are then placed in an arbor press, with the worm seal side up for squaring and centering the worm seal mounting plate 108 under the arbor press, and the seal 112 is then pressed into the worm seal mounting plate 108. The mounting plate 108 with seal 112 is then advanced or slid onto one side of the worm shaft 102 and aligned so that the screw holes 107 (Figure 9) in the worm seal mounting plate 108 align with the threaded holes 27, 87 (Figure 1) in the upper case 28 and lower case 86 assembly. Gasket sealant is then applied to the non-seal face of the worm seal mounting plate 108 and 110 and their mating surfaces on upper case 28 and lower case 86 assembly and the plates 108, 110 are attached by fasteners such as, for example, Allen head cap screws 116 (Figures 1, 9). Dowel pins in dowel pin holes are placed in lower wheel bearing housing 72 and tapped with a hammer to seat as needed. A gear oil drain plug (not shown) is installed in the lower case 86 until the top of the drain plug is flush with the exterior of the lower case 86. Dowel pin holes in the steering gear 90 are aligned with dowel pins in the lower wheel bearing housing 72 and hand pressed into place and then secured with, for example, flat head socket cap machine screws 92 and tightened in place (Figures 1, 10). A bead of sealant (not shown) is placed around the top edge of the upper case 28 and then a preferably transparent top cover 46 is placed thereon. Fasteners 48, such as Allen head screws 48 for example, are initially tightened to form a uniform and secure bond between the top cover 46 and upper case 28, but not tightened so much so that the cover 46 is pressed all of the way down to touch the upper case 28. Once the sealant has cured, usually in about one hour, the fasteners 48 can be tightened completely to form a secure connection between the top cover 46 and the upper case 28.

    [0023] Figure 12 is a top view of one embodiment of the unit 10 showing the preferably transparent top cover 46, upper case 28, worm shaft 102 and worm seal mounting plates 108 and 110. While the top cover 46 is illustrated with some transparency, it will be appreciated that he top cover 46 could also be semi-transparent, translucent, solid or a combination of the same as desired.

    [0024] Figure 13 is a cross-section taken along line 13-13 of Figure 12, and illustrates the compact construction of the unit 10. As the unit 10 is preferably to be incorporated into an AGV or the like, and in some situations the AGV would have to maneuver with very little height clearance, it is preferred that the height of the unit 10 taken along a central axis 120 through the wheel 54 and normal to the ground (not shown) is approximately four inches. Of course, other dimensions are contemplated for other environments and clearance considerations.

    [0025] Figure 14 is a perspective view taken from the bottom and Figure 15 is a perspective view taken from the side of one embodiment of certain sections of the unit 10, other sections being omitted for purposes of illustrating and demonstrating the manner in which the drive assembly 18 drives the drive wheel 54. Specifically, the worm 100 meshes with the worm gear 24 such that a rotation of the worm 100 along the axis of the worm shaft 102 causes an omnidirectional rotation of the worm gear 24 about a central axis 120 (Figure 13) of the unit 10. The rotation of the worm gear 24 results in a rotation of the bevel gear 26 through the fixed assembly of the worm gear 24 with the bevel gear 26 via the gear mounting ring 36 (see, for example, the discussion of Figure 3). The pinion gear 56 meshes with the bevel gear 26 (Figure 14) such that rotation of the bevel gear 26 causes a rotation of the pinion gear 56 about the drive shaft 58 of the wheel 54, which causes a rotation of the drive shaft 58 that drives the wheel 54 clockwise or counterclockwise (forward or backward) as desired.

    [0026] Figure 16 is a perspective view taken from the bottom of certain sections of the unit 10, other sections being omitted for purposes of illustrating and demonstrating the manner in which the wheel 54 is steered. The wheel 54 is steered through the engagement of the steering gear 90 (Figures 1, 10, 16) with the lower wheel bearing housing 72, which is fixed to the upper wheel bearing support 74 and the top wheel support 76 (see Figure 6) to form part of the wheel housing assembly 14 (Figure 1). The wheel housing assembly 14 is rotatable within the upper and lower cases 28 and 86 via bearings 30, 82, 88 (Figure 1). Rotation of the wheel 54 and the wheel housing assembly 14 (Figure 1) is accomplished by rotation of the steering gear 90 (Figures 2, 16), which causes the wheel housing assembly 14 to rotate along the central axis 120 (Figure 13) of the wheel 54 relative to the assembly of gear mounting ring 36, bevel gear 26 and worm gear 24. More specifically, omnidirectional rotation of the wheel housing assembly 14 is guided through the engagement of the pinion gear 56 with the bevel gear 26, which occurs independently of the interaction of the drive assembly 18 with the pinion gear 56. Thus, the pinion gear 56 functions to translate the rotation of the bevel gear 26 to the drive shaft 58 (see Figure 14) to drive the wheel 54, and at the same time it functions to guide the rotation of the wheel 54 relative to the upper and lower cases 28 and 86 for turning the wheel about the axis 120 (Figure 13). The driving and steering of the wheel 54 can occur independently or simultaneously as desired and depending on the control systems 200, 270 that control the drive and steering motors 250, 200 (Figure 2).

    [0027] Figure 17 illustrates one embodiment of a bottom view of an AGV 300 or the like with two drive and steering units 310, 320, each having a drive motor 312, 322 and a steering motor 314, 324. The units 310, 320 are independently arranged to provide independent driving and steering of the wheels 316, 326 relative to each other and to the AGV 300. While Figure 17 illustrates two units 310, 320, it will be appreciated that any number of units can be implemented on an AGV or the like, such as, for example, one on each corner of the AGV if desired.

    [0028] In one non-limiting embodiment, the omnidirectional drive and steering unit has a single, independently operating gear unit and housing surrounding a single, centrally located wheel, which due to the unique configuration of the unit assembly provides the ability for the wheel, and any support structure or vehicle it is a part of, to be turned for steering and drive purposes in any direction. This also includes the ability for the unit to drive and steer simultaneously, to stop and immediately reverse direction, and the ability of the wheel within the unit to be turned either clockwise or counterclockwise, in full circles or any portion thereof, either singly, or in conjunction with other similar omnidirectional drive and steering gear units. In addition, the unit is preferably designed to be very robust and to perform all of these operations while bearing a very large load and providing a significant amount of torque relative to the overall size of the unit.

    [0029] Returning to Figures 12 and 13, it will be seen that the weight from a load (not shown) placed on the top of the unit 10 is conveyed to the wheel 54 through the mounting fasteners 48 connection to the upper and lower wheel bearing supports 74, 72. This arrangement, coupled with the unique configuration of the laterally offset drive assembly 18 and driving gear arrangement that is coaxial with the central axis 120 of the wheel 54, provides for a durable, compact construction that enables a large load to be placed directly on top of the unit 10 for omnidirectional movement of the load without altering the orientation of the load relative to the unit 10. This is a significant departure from the conventional forklift-type arrangement where the load is separated from the drive and steering mechanisms.

    [0030] In one non-limiting application, an AGV which picks up an automobile by lifting under the automobile's tires, carrying an automobile forward, backward or sideways (perpendicular to an automobile's normal forwards/backwards travel orientation) through travel lanes and other components of an automated storage system, uses four coordinated versions of the omnidirectional drive and steering units to move the automobile quickly and efficiently to and from storage locations while requiring the absolute minimum possible building space and system footprint to accommodate vehicles of the size desired.

    [0031] In another non-limiting application, an AGV, with direction from other devices, sensors, measuring implements, or human intervention, implements the capabilities of the omnidirectional drive and steering units to easily and quickly shift relative location or orientation to a target item which is not situated exactly correctly relative to its normal pick up location. This system would eliminate the need for several adjustment maneuvers (similar to a three point turn) that are normally required to respond to a variation in pick up location, and could be used to handle irregularly shaped items or items which were placed imprecisely by imperfect human or mechanical operations. For example, items unloaded into an automated warehouse by human workers and not placed exactly "on center" in a loading area could be detected by sensors in the loading area and an AGV equipped with the units of present invention could shift as needed to correctly approach and acquire the target item, then shift back to center as needed to transport the acquired item to the appropriate location within the system.

    [0032] Other non-limiting examples include applications that are not fully automated but where the advanced maneuverability provided by the omnidirectional steering and drive units allows human directed vehicles to operate more efficiently than existing steering and drive systems allow. Another application allows asymmetrical items which, for example, might be long and narrow, to be transported by omnidirectional AGVs or human guided vehicles down a travel lane that was wide enough to accommodate their length (for example), then shifted sideways following a different axis into narrower storage lanes and/or storage racks without having to allow for room for turning radii to turn the AGV or load within or in to the storage aisles.

    [0033] Other non-limiting uses of an omnidirectional drive and steering unit include the movement of stage or set components in theatre performances or stage productions; platform movement in display or theatrical environments; hospital patient transport on carts or patient movement in medical scanners; movement or sorting of large items in manufacturing applications or use in factories; production machinery and materials handling and movement; bomb removal and suspicious package retrieval robots; people moving and transport mechanisms; product packaging, package handling and sorting systems; and Transfer Tables for moving and positioning large components in fabricating or manufacturing environments.

    [0034] While the present invention has been described at some length and with some particularity with respect to the several described embodiments, it is not intended that it should be limited to any such particulars or embodiments or any particular embodiment, but it is to be construed with reference to the appended claims so as to provide the broadest possible interpretation of such claims in view of the prior art and, therefore, to effectively encompass the intended scope of the invention. Furthermore, the foregoing describes the invention in terms of embodiments foreseen by the inventor for which an enabling description was available, notwithstanding that insubstantial modifications of the invention, not presently foreseen, may nonetheless represent equivalents thereto.


    Claims

    1. An omnidirectional drive and steering unit comprising:

    a) an upper case assembly (12) and a lower case assembly (16);

    b) a wheel housing assembly (14) retained in place by said upper case assembly (12) and lower case assembly (16);

    c) a drive wheel (54) housed within said wheel housing assembly (14), having a wheel drive shaft (58) and a pinion gear (56) attached to said wheel drive shaft (58);

    d) a bevel gear (26) and a worm gear (24) housed within said upper case assembly (12); and

    e) a worm assembly (98) having a worm (100) and a worm shaft (102);

    f) characterized in that when said worm shaft (102) is rotated, said worm (100) rotates and translates movement to said worm gear (24) and bevel gear (26) which translates movement to said pinion gear (56) attached to said wheel drive shaft (58), rotating said wheel drive shaft (58) driving said wheel (54).


     
    2. The omnidirectional drive and steering unit according to claim 1, wherein said lower case assembly further includes a steering and timing gear capable of 360 degree movement.
     
    3. The omnidirectional drive and steering unit according to claim 2, wherein said steering and timing gear capable of 360 degree movement is attached to said drive wheel housing and enables said drive wheel to be rotated 360 degrees to enable altering the drive direction of said drive wheel in any direction.
     
    4. The omnidirectional drive and steering unit according to claim 1, wherein said wheel housing assembly having a wheel drive shaft and a pinion gear further includes a drive shaft bearing and wheel bearing supports.
     
    5. The omnidirectional drive and steering unit according to claim 1, wherein said bevel gear and worm gear further include an outside diameter contact bearing, a gear mounting ring and a snap ring.
     
    6. A method for making an omnidirectional drive and steering unit, comprising the steps of:

    a) providing an upper case assembly (12) and a lower case assembly (16);

    b) providing a wheel housing assembly (14) retained in place by said upper case assembly (12) and lower case assembly (16);

    c) providing a drive wheel (54) housed within said wheel housing assembly (14), having a wheel drive shaft (58) and a pinion gear (56) attached to said wheel drive shaft (58);

    d) providing a bevel gear (26) and a worm gear (24) housed within said upper case assembly (12); and

    e) providing a worm assembly (98) having a worm (100) and a worm shaft (102);

    f) characterized in that when said worm shaft (102) is rotated, said worm (100) rotates and translates movement to said worm gear (24) and bevel gear (26) which translates movement to said pinion gear (56) attached to said wheel drive shaft (58), rotating said wheel drive shaft (58) driving said wheel (54).


     
    7. The method for making an omnidirectional drive and steering unit, according to claim 6, wherein said lower case assembly further includes a steering and timing gear.
     
    8. The method for making an omnidirectional drive and steering unit, according to claim 7, wherein said steering and timing gear is capable of 360 degrees of movement.
     
    9. The method for making an omnidirectional drive and steering unit, according to claim 8, wherein said steering and timing gear is attached to said drive wheel housing and enables said drive wheel to be rotated 360 degrees to enable altering the drive direction of said drive wheel in any direction.
     
    10. The method for making an omnidirectional drive and steering unit, according to claim 6, wherein said bevel gear and worm gear further include an outside diameter contact bearing, a gear mounting ring and a snap ring.
     
    11. An omnidirectional drive and steering unit comprising:

    a) a drive assembly that engages a drive gear assembly;

    b) a wheel assembly driven by the drive gear assembly and including a drive wheel (54) having a central axis, a wheel drive shaft (58) and a pinion gear (56) attached to said wheel drive shaft (58);

    c) the drive gear assembly being coaxial with the central axis; and

    d) a steering gear assembly attached to the wheel assembly and being coaxial with the central axis,

    e) wherein the drive assembly further comprises a worm (100) and a worm shaft (102);

    f) wherein the drive gear assembly further comprises a worm gear (24) attached to a bevel gear (26), the worm gear (24) meshing with the worm (100); and

    i) wherein the pinion gear (56) meshes with the bevel gear (26),

    j) characterized in that when said worm shaft (102) is rotated, said worm (100) rotates and translates movement to said worm gear (24) and bevel gear (26), which translates movement to said pinion gear (56) and wheel drive shaft (58), rotating said wheel drive shaft (58) and driving said drive wheel (54); and

    k) wherein said drive wheel (54) is driven in the forward or reverse direction depending on the rotation of the worm shaft.


     
    12. The omnidirectional drive and steering unit according to claim 11, wherein the drive assembly and the steering gear assembly are operable independently or simultaneously.
     
    13. The omnidirectional drive and steering unit according to claim 11, wherein movement of said steering gear assembly translates into movement of said wheel drive shaft gear relative to said drive gear assembly.
     
    14. The omnidirectional drive and steering unit according to claim 11, wherein the wheel assembly further comprises a wheel casing and the steering gear assembly is attached to the wheel casing of the wheel assembly.
     


    Ansprüche

    1. Omnidirektionaler Antrieb und Lenkeinheit dafür, umfassend:

    a) eine obere Gehäuseanordnung (12) und eine untere Gehäuseanordnung (16);

    b) eine Radaufnahmeanordnung (14), die durch die obere Gehäuseanordnung (12) und die untere Gehäuseanordnung (16) ortsfest gehalten wird;

    c) ein Antriebsrad (54), das innerhalb der Radaufnahmeanordnung (14) untergebracht ist, das eine Radantriebswelle (58) und ein Zahnrad (56), das an der Radantriebswelle (58) befestigt ist, aufweist;

    d) ein Kegelrad (26) und ein Schneckenrad (24), die innerhalb der oberen Gehäuseanordnung (12) untergebracht sind; und

    e) eine Schneckenanordnung (98), die eine Schnecke (100) und eine Schneckenwelle (102) aufweist;

    f) dadurch gekennzeichnet, dass, wenn die Schneckenwelle (102) gedreht wird, die Schnecke (100) dreht und die Bewegung auf das Schneckenrad (24) und das Kegelrad (26) übersetzt, das wiederum die Bewegung auf das Zahnrad (56) übersetzt, das an der Radantriebswelle (58) befestigt ist, Drehen der Radantriebswelle (58), die das Rad (54) antreibt.


     
    2. Omnidirektionaler Antrieb und Lenkeinheit dafür nach Anspruch 1, wobei die untere Gehäuseanordnung ferner ein Lenk- und Steuerrad aufweist, das zu einer 360-Grad-Bewegung fähig ist.
     
    3. Omnidirektionaler Antrieb und Lenkeinheit dafür nach Anspruch 2, wobei das Lenk- und Steuerrad, das zu einer 360-Grad-Bewegung fähig ist, an der Antriebsradaufnahme befestigt ist und dem Antriebsrad ermöglicht, um 360 Grad gedreht zu werden, um das Ändern der Antriebsrichtung des Antriebsrads in jede beliebige Richtung zu ermöglichen.
     
    4. Omnidirektionaler Antrieb und Lenkeinheit dafür nach Anspruch 1, wobei die Radaufnahmeanordnung eine Radantriebswelle aufweist und ein Zahnrad ferner ein Antriebswellenlager und einen Radlagerträger aufweist.
     
    5. Omnidirektionaler Antrieb und Lenkeinheit dafür nach Anspruch 1, wobei das Kegelrad und das Schneckenrad ferner ein Außendurchmesser-Kontaktlager, einen Radmontagering und einen Schnappring aufweisen.
     
    6. Verfahren zum Herstellen eines omnidirektionalen Antriebs und einer Lenkeinheit dafür, umfassend die folgenden Schritte:

    a) Bereitstellen einer oberen Gehäuseanordnung (12) und einer unteren Gehäuseanordnung (16);

    b) Bereitstellen einer Radaufnahmeanordnung (14), die durch die obere Gehäuseanordnung (12) und die untere Gehäuseanordnung (16) ortsfest gehalten wird;

    c) Bereitstellen eines Antriebsrades (54), das innerhalb der Radaufnahmeanordnung (14) untergebracht ist, das eine Radantriebswelle (58) und ein Zahnrad (56), das an der Radantriebswelle (58) befestigt ist, aufweist;

    d) Bereitstellen eines Kegelrades (26) und eines Schneckenrades (24), die innerhalb der oberen Gehäuseanordnung (12) untergebracht sind; und

    e) Bereitstellen einer Schneckenanordnung (98), die eine Schnecke (100) und eine Schneckenwelle (102) aufweist;

    f) dadurch gekennzeichnet, dass, wenn die Schneckenwelle (102) gedreht wird, die Schnecke (100) dreht und die Bewegung auf das Schneckenrad (24) und das Kegelrad (26) übersetzt, das wiederum die Bewegung auf das Zahnrad (56) übersetzt, das an der Radantriebswelle (58) befestigt ist, Drehen der Radantriebswelle (58), die das Rad (54) antreibt.


     
    7. Verfahren zum Herstellen eines omnidirektionalen Antriebs und einer Lenkeinheit dafür nach Anspruch 6, wobei die untere Gehäuseanordnung ferner ein Lenk- und Steuerrad aufweist.
     
    8. Verfahren zum Herstellen eines omnidirektionalen Antriebs und einer Lenkeinheit dafür nach Anspruch 7, wobei das Lenk- und Steuerrad zu einer 360-Grad-Bewegung fähig ist.
     
    9. Verfahren zum Herstellen eines omnidirektionalen Antriebs und einer Lenkeinheit dafür nach Anspruch 8, wobei das Lenk- und Steuerrad an der Antriebsradaufnahme befestigt ist und dem Antriebsrad ermöglicht, um 360 Grad gedreht zu werden, um das Ändern der Antriebsrichtung des Antriebsrads in jede beliebige Richtung zu ermöglichen.
     
    10. Verfahren zum Herstellen eines omnidirektionalen Antriebs und einer Lenkeinheit dafür nach Anspruch 6, wobei das Kegelrad und das Schneckenrad ferner ein Außendurchmesser-Kontaktlager, einen Radmontagering und einen Schnappring aufweisen.
     
    11. Omnidirektionaler Antrieb und Lenkeinheit dafür, umfassend:

    a) eine Antriebsanordnung, die in eine Antriebsradanordnung eingreift;

    b) eine Radanordnung, die durch die Antriebsradanordnung angetrieben wird und ein Antriebsrad (54) mit einer zentralen Achse aufweist, eine Radantriebswelle (58) und ein Zahnrad (56), das an der Radantriebswelle (58) befestigt ist;

    c) wobei die Antriebsradanordnung koaxial zur zentralen Achse verläuft; und

    d) eine Lenkradanordnung an der Radanordnung befestigt ist und koaxial zu der zentralen Achse verläuft,

    e) wobei die Antriebsanordnung ferner eine Schnecke (100) und eine Schneckenwelle (102) umfasst;

    f) wobei die Antriebsradanordnung ferner ein Schneckenrad (24) umfasst, das an einem Kegelrad (26) befestigt ist, wobei das Schneckenrad (24) mit der Schnecke (100) ineinander greift; und

    i) wobei das Zahnrad (56) mit dem Kegelrad (26) ineinander greift,

    j) dadurch gekennzeichnet, dass, wenn die Schneckenwelle (102) gedreht wird, die Schnecke (100) dreht und die Bewegung auf das Schneckenrad (24) und das Kegelrad (26) übersetzt, das die Bewegung auf das Zahnrad (56) und die Antriebsradwelle (58) übersetzt, wodurch die Radantriebswelle (58) gedreht wird und das Antriebsrad (54) antreibt; und

    k) wobei das Antriebsrad (54) in Vorwärts- oder Rückwärtsrichtung je nach Drehung der Schneckenwelle angetrieben wird.


     
    12. Omnidirektionaler Antrieb und Lenkeinheit dafür nach Anspruch 11, wobei die Antriebsanordnung und die Lenkradanordnung unabhängig voneinander oder gleichzeitig betrieben werden können.
     
    13. Omnidirektionaler Antrieb und Lenkeinheit dafür nach Anspruch 11, wobei die Bewegung der Lenkradanordnung zu einer Bewegung des Radantriebswellen-Zahnrades in Bezug auf die Antriebsradanordnung übersetzt.
     
    14. Omnidirektionaler Antrieb und Lenkeinheit dafür nach Anspruch 11, wobei die Radanordnung ferner eine Radaufnahme umfasst und die Lenkradanordnung an der Radaufnahme der Radanordnung befestigt ist.
     


    Revendications

    1. Unité d'entraînement omnidirectionnel et de direction comprenant :

    a) un assemblage de partie supérieure (12) et un assemblage de partie inférieure (16) ;

    b) un assemblage de logement de roue (14) maintenu en place par ledit assemblage de partie supérieure (12) et ledit assemblage de partie inférieure (16) ;

    c) une roue d'entraînement (54) logée dans ledit assemblage de logement de roue (14), ayant un arbre d'entraînement de roue (58) et un engrenage à pignons (56) fixé audit arbre d'entraînement de roue (58) ;

    d) un engrenage conique (26) et un engrenage à vis sans fin (24) logés dans ledit assemblage de partie supérieure (12) ; et

    e) un assemblage de vis sans fin (98) ayant une vis sans fin (100) et un arbre à vis sans fin (102) ;

    f) caractérisée en ce que lorsque ledit arbre à vis sans fin (102) est tourné, ladite vis sans fin (100) tourne et traduit le mouvement audit engrenage à vis sans fin (24) et audit engrenage conique (26) qui traduit le mouvement audit engrenage à pignons (56) fixé audit arbre d'entraînement de roue (58), faisant tourner ledit arbre d'entraînement de roue (58) entraînant ladite roue (54).


     
    2. Unité d'entraînement omnidirectionnel et de direction selon la revendication 1, dans laquelle ledit assemblage de partie inférieure comporte en outre un engrenage de direction et de synchronisation capable de se déplacer à 360 degrés.
     
    3. Unité d'entraînement omnidirectionnel et de direction selon la revendication 2, dans laquelle ledit engrenage de direction et de synchronisation capable de se déplacer à 360 degrés est fixé audit logement de la roue d'entraînement et permet à ladite roue d'entraînement d'être tournée à 360 degrés pour permettre de modifier le sens d'entraînement de ladite roue d'entraînement dans n'importe quel sens.
     
    4. Unité d'entraînement omnidirectionnel et de direction selon la revendication 1, dans laquelle ledit assemblage de logement de roue ayant un arbre d'entraînement de roue et un engrenage à pignons comporte en outre un palier d'arbre d'entraînement et des supports de palier de roue.
     
    5. Unité d'entraînement omnidirectionnel et de direction selon la revendication 1, dans laquelle ledit engrenage conique et ledit engrenage à vis sans fin comportent en outre un palier à contact de diamètre extérieur, un anneau de montage d'engrenage et un anneau élastique.
     
    6. Procédé de réalisation d'une unité d'entraînement omnidirectionnel et de direction, comprenant les étapes consistant à :

    a) fournir un assemblage de partie supérieure (12) et un assemblage de partie inférieure (16) ;

    b) fournir un assemblage de logement de roue (14) maintenu en place par ledit assemblage de partie supérieure (12) et ledit assemblage de partie inférieure (16) ;

    c) fournir une roue d'entraînement (54) logée dans ledit assemblage de logement de roue (14), ayant un arbre d'entraînement de roue (58) et un engrenage à pignons (56) fixé audit arbre d'entraînement de roue (58) ;

    d) fournir un engrenage conique (26) et un engrenage à vis sans fin (24) logés dans ledit assemblage de partie supérieure (12) ; et

    e) fournir un assemblage de vis sans fin (98) ayant une vis sans fin (100) et un arbre à vis sans fin (102) ;

    f) caractérisé en ce que lorsque ledit arbre à vis sans fin (102) est tourné, ladite vis sans fin (100) tourne et traduit le mouvement audit engrenage à vis sans fin (24) et audit engrenage conique (26) qui traduit le mouvement audit engrenage à pignons (56) fixé audit arbre d'entraînement de roue (58), faisant tourner ledit arbre d'entraînement de roue (58) entraînant ladite roue (54).


     
    7. Procédé de réalisation d'une unité d'entraînement omnidirectionnel et de direction, selon la revendication 6, dans lequel ledit assemblage de partie inférieure comporte en outre un engrenage de direction et de synchronisation.
     
    8. Procédé de réalisation d'une unité d'entraînement omnidirectionnel et de direction, selon la revendication 7, dans lequel ledit engrenage de direction et de synchronisation est capable de se déplacer à 360 degrés.
     
    9. Procédé de réalisation d'une unité d'entraînement omnidirectionnel et de direction, selon la revendication 8, dans lequel ledit engrenage de direction et de synchronisation est fixé audit logement de roue d'entraînement et permet à ladite roue d'entraînement d'être tournée à 360 degrés pour permettre de modifier le sens d'entraînement de ladite roue d'entraînement dans n'importe quel sens.
     
    10. Procédé de réalisation d'une unité d'entraînement omnidirectionnel et de direction, selon la revendication 6, dans lequel ledit engrenage conique et ledit engrenage à vis sans fin comportent en outre un palier à contact de diamètre extérieur, un anneau de montage d'engrenage et un anneau élastique.
     
    11. Unité d'entraînement omnidirectionnel et de direction comprenant :

    a) un assemblage d'entraînement qui s'engage dans un assemblage d'engrenage d'entraînement ;

    b) un assemblage de roue entraîné par l'assemblage d'engrenage d'entraînement et comportant une roue d'entraînement (54) ayant un axe central, un arbre d'entraînement de roue (58) et un engrenage à pignons (56) fixé audit arbre d'entraînement de roue (58) ;

    c) l'assemblage d'engrenage d'entraînement étant coaxial avec l'axe central ; et

    d) un assemblage d'engrenage de direction fixé à l'assemblage de roue et étant coaxial avec l'axe central,

    e) dans laquelle l'assemblage d'entraînement comprend en outre une vis sans fin (100) et un arbre à vis sans fin (102) ;

    f) dans laquelle l'assemblage d'engrenage d'entraînement comprend en outre un engrenage à vis sans fin (24) fixé à un engrenage pivot (26), l'engrenage à vis sans fin (24) s'engrenant avec la vis sans fin (100) ; et

    i) dans laquelle l'engrenage à pignons (56) s'engrène avec l'engrenage pivot (26),

    j) caractérisée en ce que lorsque ledit arbre à vis sans fin (102) est tourné, ladite vis sans fin (100) tourne et traduit le mouvement audit engrenage à vis sans fin (24) et audit engrenage pivot (26), qui traduit le mouvement audit engrenage à pignons (56) et audit arbre d'entraînement de roue (58), faisant tourner ledit arbre d'entraînement de roue (58) et entraînant ladite roue d'entraînement (54) ; et

    k) dans laquelle ladite roue d'entraînement (54) est entraînée vers l'avant ou vers l'arrière en fonction de la rotation de l'arbre à vis sans fin.


     
    12. Unité d'entraînement omnidirectionnel et de direction selon la revendication 11, dans laquelle l'assemblage d'entraînement et l'assemblage d'engrenage de direction peuvent fonctionner indépendamment ou simultanément.
     
    13. Unité d'entraînement omnidirectionnel et de direction selon la revendication 11, dans laquelle le mouvement dudit assemblage d'engrenage de direction se traduit par le mouvement dudit engrenage d'arbre d'entraînement de roue par rapport audit assemblage d'engrenage d'entraînement.
     
    14. Unité d'entraînement omnidirectionnel et de direction selon la revendication 11, dans laquelle l'assemblage de roue comprend en outre un carter de roue et l'assemblage d'engrenage de direction est fixé au carter de roue de l'assemblage de roue.
     




    Drawing









































    Cited references

    REFERENCES CITED IN THE DESCRIPTION



    This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

    Patent documents cited in the description