Title:
TROLLEY ASSEMBLY WITH NON-ROTATABLE AXLE
Kind Code:
A1


Abstract:
A trolley assembly for a conveyor includes a wheel assembly and a trolley arm. The wheel assembly includes a wheel that is rotatably mounted to an axle, with the axle extending along an axis of rotation of the wheel and comprising a mounting portion that is non-rotatably mounted to or at least partially received in the trolley arm. The mounting portion of the axle may be inserted into a passageway and at least partially expanded to limit retraction of the axle from the passageway, or a fastener or other retaining means may secure the axle at least partially within a passageway of the trolley arm. The mounting portion of the axle may comprise a non-cylindrical mounting portion that is received in a non-cylindrical-shaped passageway of the trolley arm.



Inventors:
Schmidt, Wayne E. (Spring Lake, MI, US)
Rathbun, Jonathan M. (Belmont, MI, US)
Frost, Charles C. (Ada, MI, US)
Application Number:
12/191348
Publication Date:
02/19/2009
Filing Date:
08/14/2008
Assignee:
FROST, INC. (Grand Rapids, MI, US)
Primary Class:
International Classes:
B61B3/00
View Patent Images:
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Primary Examiner:
KUHFUSS, ZACHARY L
Attorney, Agent or Firm:
VAN DYKE, GARDNER, LINN & BURKHART, LLP (GRAND RAPIDS, MI, US)
Claims:
1. A trolley assembly for a conveyor, said trolley assembly comprising: a wheel assembly, said wheel assembly including a wheel that is rotatably mounted to an axle, said axle extending along an axis of rotation of said wheel and comprising a mounting portion having a non-cylindrical outer surface; and a trolley arm, said trolley arm having a non-cylindrical-shaped passageway at least partially therethrough, said passageway non-rotatably receiving said mounting portion of said axle at least partially therein, wherein said axle is non-rotatably mounted to said trolley arm, while said wheel is rotatable about said axle.

2. The trolley assembly of claim 1, wherein said non-cylindrical outer surface of said mounting portion of said axle is substantially similar in shape to said non-cylindrical-shaped passageway.

3. The trolley assembly of claim 1, wherein said non-cylindrical-shaped outer surface of said mounting portion of said axle comprises a hexagonal-shaped axle and said passageway comprises a hexagonal-shaped passageway.

4. The trolley assembly of claim 1 further comprising a fastener for securing said mounting portion of said axle at least partially in said passageway to mount said wheel assembly to said trolley arm.

5. The trolley assembly of claim 4, wherein said trolley arm has a first surface at a first end of said passageway that opposes said wheel and a second surface at a second end of said passageway that is opposite said first surface, said fastener having a head portion and a fastening portion, said fastening portion engaging said axle and said head portion being at said second surface of said trolley arm when said fastener secures said axle at least partially in said passageway.

6. The trolley assembly of claim 5, wherein said axle includes a threaded fastener receptacle, said fastener comprising a threaded fastener and being threadedly received within said threaded fastener receptacle to secure said axle at least partially in said passageway.

7. The trolley assembly of claim 6, wherein said head portion of said fastener engages a washer at said second surface when said fastener is tightened in said threaded fastener receptacle of said axle.

8. The trolley assembly of claim 4, wherein said fastener includes a lubrication port and said axle includes a lubrication passageway, said lubrication port and said lubrication passageway being configured to allow lubricant to flow through said fastener and to bearings of said wheel assembly.

9. The trolley assembly of claim 1, wherein said mounting portion of said axle includes a lubrication port and said axle includes a lubrication passageway, said lubrication port and said lubrication passageway being configured to allow lubricant to flow through said axle and to bearings of said wheel assembly.

10. The trolley assembly of claim 1, wherein said axle is secured within said passageway via a portion of said axle being radially expanded to limit longitudinal movement of said axle relative to said trolley arm.

11. The trolley assembly of claim 10, wherein said portion of said axle is radially expanded to substantially correspond to a radially expanded portion of said passageway of said trolley arm.

12. The trolley assembly of claim 11, wherein said portion of said axle that is radially expanded comprises an outer end region of said mounting portion of said axle that is opposite from said wheel.

13. The trolley assembly of claim 1, wherein said axle further comprises a hub portion, said wheel being rotatably mounted to said hub portion of said axle and rotatable thereabout via at least one bearing element.

14. The trolley assembly of claim 13, wherein said hub portion comprises a generally cylindrical hub portion.

15. A trolley assembly for a conveyor, said trolley assembly comprising: a wheel assembly, said wheel assembly including at least one wheel that is rotatably mounted to a hub portion, said hub portion extending along an axis of rotation of said wheel and comprising a non-cylindrical passageway at least partially therethrough; a trolley arm; and an axle at said trolley arm, said axle comprising a mounting portion having a non-cylindrical outer surface, wherein said passageway of said hub portion non-rotatably receives said mounting portion of said axle at least partially therein, and wherein said hub portion is non-rotatably mounted to said axle, while said wheel is rotatable about said axle and said hub portion.

16. The trolley assembly of claim 15, wherein said non-cylindrical-shaped outer surface of said axle comprises a hexagonal flange and said passageway comprises a hexagonal-shaped passageway.

17. The trolley assembly of claim 15, further comprising: a bearing assembly at said wheel assembly, said bearing assembly having at least one inner race comprising a passageway therethrough; at least one recess in an inner surface of said inner race at said passageway; and wherein said hub portion defines an outer surface, said outer surface having at least one ridge corresponding to said at least one recess, said passageway of said inner race receiving said hub portion and said at least one recess receiving said at least one ridge, whereby said inner race non-rotatably receives said hub portion.

18. The trolley assembly of claim 17, wherein said hub portion is swaged to retain said at least one inner race at said hub portion.

19. The trolley assembly of claim 17, wherein said at least one inner race comprises an inner surface defining said passageway, and wherein at lease one of said outer surface of said hub portion and said inner surface of said inner race comprises a knurled surface.

20. The trolley assembly of claim 15 further comprising: an axle mount, said axle mount defining an outer surface and comprising a longitudinal passageway therethrough, said axle mount defining an inner surface at said longitudinal passageway, said axle mount having a radial passageway extending from said outer surface to said inner surface; a radial passageway in said axle; a pin; and wherein said longitudinal passageway of said axle mount receives said axle, and wherein said radial passageway of said axle mount is aligned with said radial passageway in said axle when said axle is received in said axle mount, and wherein said pin is inserted through said radial passageway of said axle mount and into said radial passageway of said axle such that a portion of said pin remains in said radial passageway of said axle mount, whereby said pin substantially prevents relative rotation of said axle in said axle mount.

21. The trolley assembly of claim 15, wherein said wheel assembly comprises two wheels, each of said wheels being rotatably mounted to a hub portion, each of said hub portions extending along an axis of rotation of said wheels and comprising a non-cylindrical passageway at least partially therethrough; and wherein said axle comprises two mounting portions, each of said mounting portions having a non-cylindrical outer surface, wherein said passageways of said hub portions non-rotatably receive said mounting portions of said axle at least partially therein, while each of said wheels is rotatable about said axle and a respective one of said hub portions.

22. The trolley assembly of claim 15, wherein said axle is swaged to retain said at least one wheel assembly at said axle.

Description:

CROSS REFERENCE TO RELATED APPLICATION

The present application claims the benefit of U.S. provisional application Ser. No. 60/955,745, filed Aug. 14, 2007, which is hereby incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates generally to trolley assemblies for conveyors of material handling systems and, more particularly, to a trolley assembly with a wheel rotatably mounted to a trolley arm or bracket for travel along an I-beam or the like of the material handling system.

BACKGROUND OF THE INVENTION

Conveyor trolleys typically have bearings between the wheel and the hub of each trolley wheel assembly to allow for smooth, generally low friction rolling of the wheel relative to the hub and trolley arm. Typically, the trolley wheels are mounted to the trolley arm via trolley brackets. Such brackets are typically manufactured with wheels that are permanently swaged in place at the bracket. Thus, the wheels are not removable from the brackets after manufacture. Such a permanent mounting arrangement makes it difficult if not impossible to service or replace a wheel on a trolley bracket.

Although it is known to bolt on a wheel to a trolley arm (such as described in U.S. Pat. No. 6,880,469, which is hereby incorporated herein by reference in its entirety), the bolt extends through the bearing assembly and through the trolley arm, where it is retained via a female fastener or nut at the outer side of the trolley arm from the wheel. Such a mounting arrangement leads to disassembly of the bearing assembly when the bolt is removed to remove the wheel from the trolley arm.

Therefore, there is a need in the art for a trolley assembly which overcomes the shortcomings of the prior art.

SUMMARY OF THE INVENTION

The present invention provides a trolley assembly that has a wheel removably mounted or attached to a trolley arm or bracket. The arm includes a non-circular-shaped passageway, and the wheel includes a correspondingly shaped or formed axle so that the wheel axle is readily inserted into and non-rotatably received in the non-circular passageway of the arm. The axle of the wheel may include internal threads so that a male fastener or bolt may be threadedly received in the axle to retain the axle within the non-circular passageway and thus to retain the axle and the wheel at the trolley arm. Optionally, the axle may be adapted or formed, such as via expansion of a portion of the axle, so as to limit retraction of the axle from the passageway of the trolley arm.

According to an aspect of the present invention, a trolley assembly for a conveyor comprises a wheel assembly and a trolley arm. The wheel assembly includes a wheel that is rotatably mounted to an axle, such as via a bearing assembly or element or device, with the axle extending along an axis of rotation of the wheel and comprising a non-cylindrical outer surface. The trolley arm has a non-cylindrical-shaped passageway therethrough, and preferably is shaped so that the outer surface of the axle substantially corresponds to and substantially mates with the inner surface of the passageway of the trolley arm when the axle is inserted into the passageway of the trolley arm. The passageway non-rotatably receives the axle at least partially therein.

Optionally, for example, the non-cylindrical-shaped outer surface of the axle may comprise a hexagonal surface of the axle and the passageway may also comprise a hexagonal-shaped passageway. Other non-cylindrical or non-circular shapes, such as regular polygonal shapes, such as a rectangular shape or the like, or such as an irregular shape, such as a shape having a radial projection or key or ridge that fits in and generally corresponds to a slot or key hole in the passageway, may be utilized for the axle and passageway to non-rotatably receive the axle within the passageway, while remaining within the spirit and scope of the present invention.

In one form, a fastener may secure the axle at least partially in the passageway to mount the wheel assembly to the trolley arm. The trolley arm has a first or inner surface at a first or inner end of the passageway that opposes the wheel and a second or outer surface at a second or outer end of the passageway that is opposite the first surface. The fastener has a head portion and a fastening portion (such as a threaded portion), whereby the fastening portion engages the axle (such as via threaded engagement in a threaded passageway or receptacle of the axle), while the head portion is at the second surface of the trolley arm when the fastener secures the axle at least partially in the passageway. A washer may be provided at the outer or second surface of the trolley arm so that the head portion of the fastener engages the washer at the second surface when the fastener is tightened in the threaded fastener receptacle of the axle.

In another form, the axle may be inserted at least partially into the passageway of the trolley arm and a portion (such as an outer end portion) of the axle may be radially expanded or flared or swaged to limit or substantially preclude retraction of the axle from the passageway of the trolley arm. For example, an outer end portion of the axle may be radially expanded to generally correspond to a radially expanded outer portion of the passageway, such that the radially expanded portion of the axle is substantially precluded from being moved longitudinally along the passageway toward the wheel.

Optionally, the axle may include a lubrication port and a lubrication passageway. The lubrication port and the lubrication passageway are configured to allow lubricant to flow through the axle and to bearings or bearing elements (which facilitate rotation of the wheel about the axle) of the wheel assembly. Thus, the bearing elements may be readily lubricated to ease or enhance rotation of the wheel about the axle.

According to another aspect of the present invention, a trolley assembly for a conveyor includes a wheel assembly and a trolley arm. The wheel assembly includes a wheel that is rotatably mounted to a hub or hub portion that extends along an axis of rotation of the wheel and includes a non-cylindrical passageway. The hub portion is coupled to an axle at the trolley arm. The axle comprises a mounting portion with a non-cylindrical outer surface for engaging the non-cylindrical passageway so that the hub portion is non-rotatably mounted to the axle while the wheel remains rotatable about the axle and the hub portion.

Therefore, the present invention provides a trolley assembly that has a removable wheel assembly, where the wheel assembly may be readily attached to and/or removed from the trolley arm via a single fastener. The wheel assembly includes an axle that is non-rotatably secured at the trolley arm, whereby the wheel rotates about the axle via one or more bearing elements (such as ball bearings or journal bearings or the like). The wheel assembly may be secured to the trolley arm, and with the axle non-rotatably secured to the trolley arm, such as via a threaded fastener that is at least partially received in a threaded fastener receptacle of the axle, or such as via a swaged axle to trolley construction or via other mounting means that limit or substantially preclude longitudinal movement of the axle along the passageway of the trolley. Thus, the wheel assembly is rotatably mounted to the trolley arm via a non-rotatable mounting or attachment of the axle portion to the trolley arm. The non-circular axle and passageway limits or substantially precludes relative rotation of the axle portion within the trolley arm, even if the bearing were to lock up. Optionally, removal and/or replacement of the wheel assembly (such as may be necessitated by worn wheels or worn bearings or bearing elements) may be facilitated via the threaded fastener attachment means without requiring removal and replacement of the entire trolley arm or bracket.

These and other objects, advantages, purposes and features of the present invention will become apparent upon review of the following specification in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a trolley assembly in accordance with the present invention;

FIG. 2 is a sectional view of the trolley assembly of FIG. 1, as assembled and movable along a beam of a conveyor assembly;

FIG. 3 is a side elevation of another trolley assembly in accordance with the present invention;

FIG. 4 is a sectional view of the trolley assembly of FIG. 3;

FIG. 5 is a partially-exploded perspective view of a portion of a trolley assembly in accordance with the present invention;

FIG. 6A is a perspective view of a wheel assembly useful with the trolley assembly of FIG. 5;

FIG. 6B is a side elevation of the wheel assembly of FIG. 6A;

FIG. 7 is a perspective view of another trolley assembly of the present invention, having a pair of double-wheel assemblies;

FIG. 8 is an exploded perspective view of portions of a double wheel assembly in accordance with the present invention;

FIG. 9 is a top plan view of the double wheel assembly of FIG. 8;

FIG. 10 is a sectional view taken along the section designated X of FIG. 9;

FIG. 11 is an exploded view of another double wheel assembly in accordance with the present invention; and

FIG. 12 is a perspective view of another trolley assembly in accordance with the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the drawings and the illustrative embodiments depicted therein, a trolley assembly 10 includes a wheel assembly 12, a trolley arm or bracket 14, and a fastener or attachment or securing element 16 (FIGS. 1 and 2). Wheel assembly 12 includes a wheel 18, which is rotatably mounted to an axle 20, which extends along an axis of rotation of wheel 18. Trolley arm 14 includes a passageway 15 therethrough for at least partially non-rotatably receiving axle 20 therein. The axle and passageway are generally correspondingly shaped in a non-circular or non-cylindrical manner to limit relative rotation therebetween. Fastener 16 secures or retains axle 20 in passageway 15 to mount wheel assembly 12 to trolley arm 14, as discussed below. The axle 20 is thus secured to the trolley arm 14, whereby wheel 18 rotates about axle 20 as the trolley assembly 10 and trolley arm 14 travel along an I-beam track or rail 22 (FIG. 2) or the like of a trolley conveyor system of a material handling system. The non-circular axle and passageway construction limits or substantially precludes relative rotation of the axle portion within the trolley arm, even if the bearing were to lock up.

Wheel 18 is rotatably mounted to axle 20 via a bearing assembly or device 24, such as a bearing device comprising bearings or bearing elements (not shown). Such bearings or bearing elements may comprise any suitable element, such as ball bearings or journal bearings or other known bearings, or such as journal bearings of the types described in U.S. Pat. No. 6,880,469, which is hereby incorporated herein by reference in its entirety, without affecting the scope of the present invention. Bearing device 24 may have an inner portion and an outer portion, which is rotatable about the inner portion via the bearing elements (such as ball bearings between an inner race and an outer race or the like). The inner portion may be fixedly secured to or integral with the axle 20, while the outer portion is fixedly secured to or integral with the wheel 18, such that the wheel 18 and outer portion are rotatable about the inner portion and axle 20 as the trolley assembly travels along the beam or track or rail 22. Optionally, the axle may be unitarily formed or integral with the inner portion of the bearing device and/or the wheel may be unitarily formed or integral with the outer portion of the bearing device, whereby the wheel rotates about the axle via sliding engagement between the wheel and axle or via sliding or rolling engagement with one or more bearing elements or the like at the mating or engaging surfaces of the wheel and/or axle. The axle 20 thus may be integral with or fixedly secured to the inner portion or race or hub of the bearing device and may extend from the bearing device and along the axis of rotation of the wheel for attachment to the trolley arm.

The wheel assembly 12 includes an inner stop surface 26, such as generally at the junction of the axle 20 and the bearing device 24 to limit insertion of axle 20 into passageway 15 of trolley arm 14, as discussed below. In the illustrated embodiment, stop surface 26 is at an inner surface of bearing device 24, such as at an inner surface of the inner portion or hub of the bearing device, and axle 20 extends therefrom to provide a non-rotatable mounting arrangement of the axle 20 and a portion of the bearing device 24, whereby wheel 18 and the outer portion of the bearing device rotate about the axle 20 via the bearing element or elements of the bearing device 24.

Axle 20 thus extends along the axis of rotation of wheel 18, with wheel 18 being rotatable relative to the axle via the bearing device or element or elements 24. Axle 20 has a non-circular cross section or is a non-cylindrical shape so that axle 20 may be non-rotatably received in the non-circular or non-cylindrical passageway 15. In the illustrated embodiment, axle 20 is hexagonal-shaped, but other shapes, such as a rectangular shape or any other non-circular shape may be utilized for the shape or configuration of the outer surface or structure of the axle, without affecting the scope of the present invention. For example, the axle and passageway may have a non-cylindrical or non-circular shape as will be described below, such as a regular polygonal shape, such as a rectangular shape or hexagonal shape or the like, or may have an irregular shape, such as a shape having a radial projection or key or ridge that fits in and generally corresponds to a slot or key hole in the passageway, in order to non-rotatably position the axle within the passageway, while remaining within the spirit and scope of the present invention.

Axle 20 includes an internally threaded passageway 20a at least partially therealong. Threaded passageway 20a is open at an outer end of the axle 20 (at the distal end from the bearing device 24) so as to be adapted to receive a threaded fastener 16 therein. A lubrication passageway 20b may extend along axle 20, such as from an inner end of the threaded passageway 20a to the bearing device 24. Lubrication passageway 20b allows for lubricant (such as oil or grease or the like) to flow through axle 20 and to the bearing elements of the bearing device 24, such as lubricant that is applied or injected or pumped into and through a lubrication passageway 16a of fastener 16 when fastener 16 is received in threaded passageway 20a of axle 20 to secure the wheel assembly 12 to the trolley arm 14, as discussed below.

Trolley arm 14 includes a wheel mounting portion 14a, through which axle receiving passageway 15 is formed, and a drive chain connecting portion 14b, which is connectable to a drive chain or conveyor chain for moving the trolley along the track 22, as is known in the art. Drive chain connecting portion 14b is a curved arm element that extends downward from wheel mounting portion 14a and includes a notch 14c for connecting to a link of a chain or the like. Drive chain connecting portion 14b may be configured to attach to a load bar or the like, such as is known in the art and such as by utilizing known aspects or by utilizing aspects of the trolley attachment described in U.S. Pat. No. 7,334,527, which is hereby incorporated herein by reference in its entirety. Passageway 15 is formed through wheel mounting portion 14a and is a non-circular or non-cylindrical passageway (and thus is configured to have a non-cylindrical inner surface) so as to non-rotatably receive non-circular axle 20 therein. In the illustrated embodiment, passageway 15 is hexagonal-shaped, but other shapes, such as a rectangular shape or any other non-circular shape may be utilized, without affecting the scope of the present invention.

In the illustrated embodiment, fastener 16 comprises a threaded male fastener, such as a bolt or the like. Fastener 16 thus has a threaded portion 16b, with a head portion 16c at one end of the threaded portion 16b. Desirably, fastener 16 includes lubrication passageway 16a formed through head portion 16c and through threaded portion 16b to provide a continuous passageway through the length of fastener 16, from the outer surface of head portion 16c to the opposite end of threaded portion 16b, such as can be seen in FIG. 2. Preferably, fastener 16 includes a fitting or nipple 28 at the outer end of passageway 16a at head portion 16c, so that lubricant or grease or the like may be readily fed or pumped or injected into passageway 16a and thus into and through passageway 20b of axle 20 and into bearing device 24, so as to ease lubrication of the bearing elements of the wheel assembly 12. In the illustrated embodiment, fitting 28 is threaded into a threaded portion of the lubrication passageway, but other types of fittings may be otherwise secured or attached at the end of the lubrication passageway at the head portion 16c of the fastener 16, without affecting the scope of the present invention.

The trolley assembly 10 thus may be readily assembled via insertion of the axle into the passageway of the trolley arm and tightening of a single fastener. The wheel assembly 12, which includes the wheel 18, bearing device 24 and axle 20, may be readily connected to or attached to the trolley arm 14 via insertion of axle 20 into passageway 15 of arm 14. Axle 20 (which preferably substantially corresponds to or mates with the inner surface of the passageway) may be inserted substantially into and along passageway 15 until stop surface 26 contacts an inner or opposed surface 15a of the wheel mounting portion 14a of trolley arm 14, thereby limiting further insertion of axle 20 into passageway 15. Fastener 16 is then threaded into threaded passageway 20a to secure the wheel assembly to the trolley arm. Optionally, and preferably, a washer 30 is provided at fastener 20 and at the outer surface 15b of wheel mounting portion 14a of trolley arm 14. Thus, as fastener 16 is tightened, fastener 16 pulls axle 20 into passageway 15 and head portion 16c engages washer 30, which in turn engages the outer surface of wheel mounting portion 14a of trolley arm 14, such that further tightening of fastener 16 functions to substantially clamp the wheel assembly to the trolley arm. Because the axle extends from the end of the bearing device, the clamping of the wheel assembly to the trolley via tightening of the fastener is accomplished without clamping the bearing elements of the bearing device, such that the wheel is substantially freely rotatable about the axle.

When assembled in this manner, the axle 20 of wheel assembly 12 is non-rotatably received in axle passageway 15 of trolley arm 14 via the non-circular passageway or bore and the corresponding mating axle, while the threaded fastener functions to clamp the axle and wheel assembly to the trolley arm. If lubrication is desired or needed for maintenance of the bearing device or elements, lubricant may be dispensed through the fitting 28 at head portion 16c of fastener 16 to provide lubrication to the bearing elements via the lubrication passageways 16a and 20b of fastener 16 and axle 20, respectively. If the bearing elements and/or the wheel wears and needs replacement, the fastener 16 may be removed from axle 20 so that axle 20 may be withdrawn from passageway 15 to remove the wheel assembly 12 from the trolley arm 14. A new wheel assembly may then be mounted to or fastened to the trolley arm to repair or maintain the trolley assembly.

Therefore, the present invention provides a trolley assembly for a conveyor or material handling system that has a trolley wheel and bearing assembly that is removably mounted to the trolley arm. The axle of the wheel assembly may be non-rotatably received within a passageway through the trolley arm or bracket and may be secured therein, such as via a threaded fastener or via other fastener elements or fastening means. The wheel and/or bearing device or elements thus may be readily mounted to a trolley arm and may be readily removed from a trolley arm to substantially ease maintenance or repair/replacement of the wheel and/or bearing elements during use of the trolley assembly. The non-circular axle and passageway construction and engagement limits or substantially precludes relative rotation of the axle portion within the trolley arm, even if the bearing were to lock up.

Optionally, other means of connecting the wheel assembly to a trolley arm may be implemented, without affecting the scope of the present invention. Optionally, the wheel assembly may have a swaged wheel-to-trolley construction, where the hub portion of the wheel assembly is non-removably secured to the trolley arm via a flared portion of the hub axle engaging a correspondingly formed region of the trolley arm. For example, a non-circular axle of a wheel assembly may be pressed or inserted into a correspondingly non-circular passageway of the trolley arm and the end of the axle may be flared outwardly to limit or substantially preclude retraction of the axle from the trolley arm, in order to non-rotatably secure the wheel assembly to the trolley arm.

For example, and with reference to FIGS. 3 and 4, a trolley assembly 110 includes a wheel assembly 112 and a trolley arm or bracket 114, where the wheel assembly 112 includes an axle 120 for mounting the wheel to the trolley arm (FIGS. 1 and 2). Axle 120 includes a hub portion 120a, which has the wheel 118 and bearing assembly 124 rotatably mounted thereto, and a shaft portion or mounting portion 120b, which is non-rotatably received in a passageway 115 through trolley arm 114. Wheel 118 is rotatably mounted to hub portion 120a of axle 120, which extends along an axis of rotation of wheel 118, such as via bearing assembly 124.

Passageway 115 of trolley arm 114 is configured to at least partially non-rotatably receive mounting portion 120b of axle 120 therein, such as in a similar manner as described above. In the illustrated embodiment, passageway 115 is a pentagonal-shaped passageway and mounting portion 120b of axle 120 is a pentagonal-shaped shaft or axle portion so that axle is non-rotatably received within passageway 115, thereby limiting or substantially precluding any relative rotation between axle 120 and trolley arm 114, even if the bearing were to lock up. The axle 120 is thus non-rotatably secured to the trolley arm 114, whereby wheel 118 rotates about axle 120 as the trolley assembly 110 and trolley arm 114 travel along an I-beam track or rail or the like of a trolley conveyor system of a material handling system.

In the illustrated embodiment, the outer end 120c of mounting portion 120b is flared (not shown in FIG. 4) radially outwardly so as to limit or substantially preclude retraction of the axle portion from the passageway of trolley arm 114. As can be seen in FIG. 4, an outer region 115a of passageway 115 of trolley arm 114 is flared radially outwardly, while the outer end or region 120c of mounting portion 120b of axle 120 may be partially hollowed. The hollowed end region 120c of mounting portion 120b allows a tool to be inserted at least partially into the hollowed end region 120c of mounting portion 120b and radially expand the outer hollowed end region 120c to substantially correspond to the flared outer region 115a of passageway 115. Thus, after the mounting portion 120b of axle 120 is inserted into passageway 115 of trolley arm 114, the outer hollowed end region 120c may be flared radially outwardly to limit or substantially preclude retraction of the mounting portion and axle from the trolley arm. The axle thus is non-rotatably and non-removably secured to the trolley arm, while the wheel is rotatable about the hub portion 120a of the secured axle 120.

In the illustrated embodiment, wheel 118 is rotatably mounted to hub portion 120a of axle 120 via bearing assembly or device 124, such as a bearing device comprising bearings or bearing elements 124a that are movably received at inner and outer bearing races or the like. Such bearings or bearing elements may comprise any suitable element, such as ball bearings or journal bearings or other known bearings, or such as journal bearings of the types described in U.S. Pat. No. 6,880,469, which is hereby incorporated herein by reference in its entirety, without affecting the scope of the present invention. As shown in FIG. 4, bearing assembly 124 may have an inner race or portion 124b and an outer race or portion 124c, which is rotatable about the inner portion via the bearing elements (such as ball bearings 124a between an inner race and an outer race or the like). The inner portion may be fixedly secured to or integral with the hub portion 120a of axle 120, while the outer portion is fixedly secured to or integral with the wheel 118, such that the wheel 118 and outer portion are rotatable about the hub portion 120a and axle 120 as the trolley assembly travels along the beam or track or rail. Optionally, the axle may be unitarily formed or integral with the inner portion of the bearing device and/or the wheel may be unitarily formed or integral with the outer portion of the bearing device, whereby the wheel rotates about the axle via sliding engagement between the wheel and axle or via sliding or rolling engagement with one or more bearing elements or the like at the mating or engaging surfaces of the wheel and/or axle (such as described in U.S. Pat. No. 6,880,469, which is hereby incorporated herein by reference in its entirety). The axle 120 thus may be integral with or fixedly secured to the inner portion or race or hub of the bearing device and may extend from the bearing device and along the axis of rotation of the wheel for attachment to the trolley arm.

The wheel assembly 112 includes shields 126a, 126b at opposite sides of the wheel assembly to substantially seal the bearing assembly within the wheel assembly. In the illustrated embodiment, a contact seal 127a (such as a rubber or urethane seal of the like) is attached to the wheel and rotates with the wheel, while the hub has a seal seat 127b that does not rotate with the wheel. The contact seal 127a and seal seat 127b thus slidingly mate together to substantially seal the wheel assembly to limit and substantially preclude water or dirt or debris or contaminant intrusion into the bearing assembly during operation of the material handling system.

Axle 120 thus extends along the axis of rotation of wheel 118, with wheel 118 being rotatable relative to the axle via the bearing device 124. Mounting portion 120b of axle 120 has a non-circular cross section or is a non-cylindrical shape so that axle 120 may be non-rotatably received in the correspondingly non-circular or non-cylindrical passageway 115. In the illustrated embodiment, mounting portion 120b of axle 120 is pentagonal-shaped, but other shapes, such as a rectangular shape or any other non-circular shape may be utilized for the shape or configuration of the outer surface or structure of the axle, without affecting the scope of the present invention.

In the illustrated embodiment, a lubrication passageway 120d extends along axle 120, such as from an inner end of the hub portion 120a to the outer end 120c of the mounting portion 120b. Lubrication passageway 120d allows for lubricant (such as oil or grease or the like) to flow through axle 120 and to the bearing elements of the bearing device 124, such as lubricant that is applied or injected or pumped into and through the lubrication passageway 120d of axle 120. Preferably, mounting portion 120b of axle 120 includes a fitting or nipple 128 at the outer end of passageway 120d, so that lubricant or grease or the like may be readily fed or pumped or injected into passageway 120d and thus into and through axle 120 and into bearing device 124, so as to ease lubrication of the bearing elements of the wheel assembly 112. In the illustrated embodiment, fitting 128 is threaded into a threaded portion of the lubrication passageway, but other types of fittings may be otherwise secured or attached at the end of the lubrication passageway of the axle, without affecting the scope of the present invention.

The wheel assembly 112, which includes the wheel 118, bearing device 124 and axle 120, thus may be connected or attached to the trolley arm 114 via insertion of the mounting portion 120b of axle 120 into the passageway 115 of the trolley arm 114, and expansion of end portion 120c of axle 120 after insertion. When assembled in this manner, the axle 120 of wheel assembly 112 is non-rotatably received in axle passageway 115 of trolley arm 114 via the non-circular passageway or bore and the corresponding mating axle. If lubrication is desired or needed for maintenance of the bearing device or elements, lubricant may be dispensed through the fitting 128 to provide lubrication to the bearing elements via the lubrication passageway 120d of axle 120.

Therefore, the present invention provides a trolley assembly for a conveyor or material handling system that has a trolley wheel and bearing assembly that is removably mounted to the trolley arm. The axle of the wheel assembly may be non-rotatably received within a passageway through the trolley arm or bracket and may be secured therein, such as via a threaded fastener or via other fastener elements or fastening means, such as via a swaged axle-to-trolley construction or the like. The non-circular axle and passageway construction and engagement limits or substantially precludes relative rotation of the axle portion within the trolley arm, even if the bearing were to lock up.

Optionally, and with reference to FIGS. 5 and 12, a trolley assembly 210 includes one or more wheel assemblies 212 mounted at a trolley arm or arms or bracket 214. The trolley assembly 210 includes an axle 220 (FIG. 5) for mounting each wheel assembly 212 to the trolley arm 214. Axle 220 includes a non-circular or non-cylindrical flange 215 at a base of axle 220 and generally at arm 214. Wheel assembly includes a hub portion 221 that receives axle 220 therein when wheel assembly 212 is mounted on arm 214. In the illustrated embodiment, hub portion 221 includes a generally cylindrical portion 221a, with a non-circular or non-cylindrical female anti-rotation feature 221b at its end that opposes arm 214. The anti-rotation feature 221b is formed to generally correspond with the non-circular flange 215 of axle 220 and to have dimensions complimentary to or corresponding with the dimensions of non-cylindrical flange 215. Thus, flange 215 is non-rotatably received into anti-rotation feature 221b when hub portion 221 receives axle 220 and is installed at axle 220.

As shown in FIG. 5, hub portion 221 receives the other components of wheel assembly 212, which includes a pair of inner races or portions 224b that receive a set of ball bearings 224a surrounded by an outer race or portion 218. Wheel assembly 212 is thereby rotatably mounted to hub portion 221, which is non-rotatably mounted to axle 220. When wheel assembly 212 is assembled with hub portion 221, and hub portion 221 is fully seated on axle 220 such that anti-rotation feature 221b receives non-cylindrical flange 215, an outer end 220a of axle 220 may be flared or swaged to limit or substantially preclude removal of the hub portion 221 (and thus wheel assembly 212) from axle 220.

Optionally, and for example, as shown in FIG. 5, the non-cylindrical flange 215 may comprise a hexagonal surface of the axle 220 and the non-cylindrical female anti-rotation feature 221b may also comprise a hexagonal shape. Other non-cylindrical or non-circular shapes, such as regular polygonal shapes, such as a rectangular shape or the like, may be utilized for the non-cylindrical flange and non-cylindrical female anti-rotation feature to non-rotatably receive the hub portion of the wheel assembly, while remaining within the spirit and scope of the present invention.

In the illustrated embodiment, trolley arms 214 include a wheel mounting portion 214a, to which axles 220 and wheel assemblies 212 are attached, and a drive chain connecting portion 214b, which is connectable to a drive chain or conveyor chain for moving the trolley along a track, as is known in the art. Drive chain connecting portion 214b is a curved arm element that extends downward from wheel mounting portion 214a and includes a passageway or hole 214c (FIG. 5) for receiving a fastener therethrough for retaining the arms 214 and a trolley engaging member 236 together (FIG. 12). Trolley arms 214 may be clamped or fastened together to entrap or lock trolley-engaging member 236 therebetween, such as by placing threaded fasteners (not shown) through holes 214c and tightening threaded nuts thereon.

Optionally, and with reference to FIGS. 6A and 6B, a wheel assembly 212′ may comprise a hub portion 221′ with an inner surface 221a′ defining one or more recesses or channels 221b′ that are keyed or positioned to match corresponding ridges or radial projections on an outer surface of an axle on a trolley arm or bracket (not shown in FIGS. 6A and 6B). Channels 221b′ receive or engage corresponding ridges on an axle when hub portion 221′ is positioned on the axle, so that hub portion 221′ is non-rotatable with respect to the axle. Optionally, channels may be located at the axle and corresponding radial projections or ridges may be located at the inner surface of the hub portion in order to prevent rotation between the axle and hub portion. Thus, the wheel assembly may be non-rotatably mounted to a shaft or axle of a trolley arm or the like, such as in a similar manner as described above. The wheel assembly and trolley arms or brackets may otherwise be similar to the wheel assemblies and arms discussed above, such that a detailed discussion of the wheel assemblies and arms need not be repeated herein.

Optionally, and with reference to FIGS. 7-10, a trolley assembly 310 includes one or more double wheel assemblies 311 for supporting the trolley assembly 310 along a track, a rail, or other support surface. Double wheel assemblies 311 comprise a pair of wheel assemblies 312 rotatably mounted at opposite ends 320a of an axle 320. Wheel assemblies 312 may be installed at axle 320, and the axle ends 320a flared or swaged, as best shown in FIGS. 8 and 10, to retain the wheel assemblies thereon. Optionally, the wheel assemblies may include hub portions 321 with non-cylindrical female anti-rotation recesses or features 314a for engaging non-cylindrical flanges 315 on axle 320, such as in a similar manner as described above. Flanges 315 and female anti-rotation features 314a may be similar to hub portions 221 and features 221b, with hub portions 321 being non-rotatable with respect to axle 320, such that a detailed explanation of the assembly and function of wheel assemblies 312 and axle 320 need not be repeated herein. Optionally, axle 320, flanges 315, and/or hub portions 321 may be knurled or roughened or grooved to further prevent relative rotation between axle 320 and hub portions 321 when axle 320 is flared or swaged.

Axle 320 is non-rotatably installed at a longitudinal passageway in an axle mount 336, which may be mounted at trolley assembly 310 (FIGS. 7 and 8). An anti-rotation or locking or shear pin 338 may be partially inserted into a radial recess or hole 340 (FIG. 10) in axle 320 to prevent rotation of axle 320 in axle mount 336. A radial channel or slot 342 in axle mount 336 extends from an outer surface of the axle mount to the longitudinal passageway and is generally aligned with hole 340 to permit insertion and removal of pin 338 from axle 320 via slot 342 (FIGS. 8-10). Because only a portion of pin 338 is inserted into hole 340 of axle 320, another portion of pin 338 protrudes into slot 342 of axle mount 336 when pin 338 is installed, so that axle 320 is prevented from rotating with respect to axle mount 336. The shear strength of pin 338 may be selected to be relatively high so that, in the event that a bearing assembly of wheel assembly 312 were to seize or lock, pin 338 may remain intact and prevent relative rotation between axle 320 and axle mount 336. Alternatively, the shear strength of pin 338 may be selected to be relatively low so that, in the event that a bearing assembly of wheel assembly 312 were to seize or lock, pin 338 would fracture in shear and permit axle 320 to rotate with respect to mounting member 314a until the fractured pin could be replaced with a new pin.

Optionally, and with reference to FIG. 11, a wheel assembly, such as a double wheel assembly 411, may comprise one or more inner races 424b, each with an inner surface 430 defining a recess or slot or key hole 432 that receives and generally corresponds to a radial projection or key or ridge 434 on an outer surface of a hub portion 421 on a trolley arm or bracket (not shown). In the illustrated embodiment, each hub portion 421 includes a female anti-rotation feature 421a that fits over an axle 420 and engages a non-circular or non-cylindrical flange 415 at a base of axle 420 to prevent relative rotation between hub portion 421 and axle 420, such as in a similar manner as described above. Axle 420 is received in an axle mount 436 and may be limited or substantially precluded from rotating in the axle mount such as, for example, with a shear pin or the like. Optionally, inner surfaces 430 of inner races 424b may be grooved or knurled or roughened to provide additional resistance to relative rotation between inner races 424b and hub portion 421 when an outer end 421b of hub portion 421. Outer end 421b is flared or swaged radially outward into contact with inner surfaces 430 of inner races 424b. Alternatively, or additionally, the axle 420 may be knurled or roughened to engage smooth or roughened inner surfaces of the inner races during flaring or swaging of the axle end.

Therefore, the present invention provides a trolley assembly for a conveyor or material handling system that has a single or double wheel assembly for which rotation is permitted only by the wheel and/or bearing assembly. The wheel assemblies and at least a portion of the bearing assemblies rotate about a rotationally-fixed hub portion, which is non-rotatably coupled to an axle, which itself is non-rotatably coupled to a trolley arm. The axle includes a non-cylindrical flange, such as a hexagonal-shaped flange, that engages a correspondingly-shaped non-cylindrical female anti-rotation feature on the hub portion. When the hub portion is installed on the axle, the female anti-rotation feature engages the non-cylindrical flange to prevent rotation of the hub portion on the axle. Optionally, the hub portion and axle may be complimentarily non-cylindrical to prevent rotation. For example, the hub portion may include one or more slots or grooves that engage corresponding ridges or keys on the axle to prevent rotation of the hub portion. The axle may be non-rotatably received in a passageway through an axle mount, such as with a pin that is driven radially through a slot in the axle mount and partially into a radial hole in the axle. One or more inner races may be non-rotatably mounted to the hub portion, such as with slots or grooves that engage corresponding ridges or keys on an outer surface of the hub portion, or with knurling or roughened surfaces that are pressed or swaged together. The wheel and/or bearing device or elements thus may be non-rotatably mounted to an axle at the trolley arm, which limits or substantially precludes relative rotation of the hub portion on the axle portion, inner races on the hub portion, and the axle within the trolley arm, even if the bearing were to seize or lock up.

Changes and modifications in the specifically described embodiments may be carried out without departing from the principles of the present invention, which is intended to be limited only by the scope of the appended claims, as interpreted according to the principles of patent law.