WHEEL ASSEMBLY FOR MATERIAL HANDLING VEHICLE

Abstract

A wheel assembly for an outrigger of a material handling vehicle, comprising a first axle, a first wheel mounted on the first axle and a second wheel mounted on the first axle, whereby the first wheel and the second wheel rotate independently, and a second axle, a first wheel mounted on the second axle and a second wheel mounted on the second axle, whereby the first wheel and the second wheel rotate independently, wherein the first axle and the second axle are mounted on the outrigger, in tandem.

Claims

1. A wheel assembly for an outrigger of a material handling vehicle, comprising: a first axle, a first wheel mounted on the first axle and a second wheel mounted on the first axle, whereby the first wheel and the second wheel rotate independently; a second axle, a first wheel mounted on the second axle and a second wheel mounted on the second axle, whereby the first wheel and the second wheel rotate independently; wherein the first axle and the second axle are mounted on the outrigger, in tandem.

2. The wheel assembly of claim 1, wherein a distance between the first axle and the second axle has a value of X, and a distance between an outside of the first wheel and an outside of the second wheel on the first axle has a value of Y, and X/Y is between 0.5 and 1.3.

3. The wheel assembly of claim 2, wherein the first axle has a first end and a second end and the second axle has a first end and a second end, and the wheel assembly further comprises (i) a first bracket engaging the first end of the first axle and the first end of the second axle, and (ii) a second bracket engaging the second end of the first axle and the second end of the second axle, whereby the first bracket and the second bracket are parallel to each other and perpendicular to the first axle and second axle, and whereby the first and second brackets can be pivotally mounted on the outrigger.

4. The wheel assembly of claim 3, further comprising a shaft having a first end engaging the first bracket and a second end engaging the second bracket, and the wheel assembly can be mounted on the outrigger, whereby the wheel assembly pivots around the shaft.

5. The wheel assembly of claim 3, wherein the first bracket has a first outwardly facing projection and the second bracket has a second outwardly facing projection and the first projection and the second projection can engage the outrigger, whereby the wheel assembly pivots around the first and second projections.

6. The wheel assembly of claim 3, whereby the wheel assembly pivots at a point, and the first axle and the second axle are at an angle of 30 to 180 relative to the pivot point.

7. The wheel assembly of claim 1, further comprising a third wheel mounted on the first axle, and the third wheel rotates independently of the first and second wheels of the first axle.

8. The wheel assembly of claim 7, further comprising a third wheel mounted on the second axle, and the third wheel rotates independently of the first and second wheels on the second axle.

9. The wheel assembly of claim 7, wherein a distance between the first axle and the second axle has a value of X, and a distance between an outside of the first wheel and an outside of the third wheel on the first axle has a value of Y, and X/Y is between 0.5 and 1.3.

10. The wheel assembly of claim 9, wherein the first axle has a first end and a second end and the second axle has a first end and a second end, and the wheel assembly further comprises (i) a first bracket engaging the first end of the first axle and the first end of the second axle, and (ii) a second bracket engaging the second end of the first axle and the second end of the second axle, whereby the first bracket and the second bracket are parallel to each other and perpendicular to the first axle and second axle, and whereby the first and second brackets can be pivotally mounted on the outrigger.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] FIG. 1 is a side view of a material handling vehicle of the type for use with the wheel assembly of the present invention.

[0027] FIG. 2 is an isometric view of the wheel assembly of the present invention having a bracket with projections to engage the leg of a material handling vehicle.

[0028] FIG. 3 is an isometric view of the wheel assembly of the present invention having brackets with a shaft to engage the leg of a material handling vehicle.

[0029] FIG. 4 is a cross-sectional view of a wheel assembly showing the measurement of X (the distance between the first axle and the second axle) and Y (the aggregate width of the wheels).

[0030] FIG. 5 is a side elevation view of the wheel assembly of FIG. 3, illustrating the relative distances of the first axle and second axle from the pivot point of the assembly.

[0031] FIGS. 6-12 depict examples of Class I to Class VII powered industrial trucks according to the United States Department of Labor Occupational Safety and Health Administration (OSHA).

DETAILED DESCRIPTION OF THE INVENTION

[0032] Without intending to limit the scope of the invention, the preferred embodiments and features are hereinafter set forth. All the United States patents and published patent applications cited in the specification are incorporated herein by reference. As used herein, the term wheel is intended to encompass a tire, which may be a solid elastomer, such as a polyurethane, a rim on which the tire is mounted, and a set of bearing within the rim.

[0033] As referred to herein, the term powered industrial truck means a mobile, power-propelled truck used to carry, push, pull, lift, stack, or tier material. Vehicles that are used for earth moving and over-the-road hauling are excluded. Under OSHA regulations, there are seven classes of powered industrial trucks: [0034] Class I: Electric Motor, Sit-down Rider, Counter-Balanced Trucks (Solid and Pneumatic Tires). Powered industrial trucks in this class are electrically powered and are typically used indoors on flat, even surfaces. They have cushion or pneumatic tires. [0035] Class II: Electric Motor Narrow Aisle Trucks (Solid Tires). Powered industrial trucks in this class are electrically powered and designed for tight warehouse aisles. They are high-lift machines, often used in distribution centers and warehouses. They are designed to operate in narrow aisle stacking areas where Class I and Class III trucks cannot operate. [0036] Class III: Electric Motor Hand Trucks or Hand/Rider Trucks (Solid Tires). Powered industrial trucks in this class are hand-controlled (either walk-behind or operated on a small platform) and used for low-lift applications, e.g., pallet jacks. [0037] Class IV: Internal Combustion Engine Trucks (Solid Tires). Powered industrial trucks in this class include an internal combustion engine and are suited for indoor use on smooth floors. They are typically used for moving materials onto and off of trucks and for warehousing. [0038] Class V: Internal Combustion Engine Trucks (Pneumatic Tires). Powered industrial trucks in this class have an internal combustion engine and are designed for rough surfaces outdoors. They are commonly used in loading docks and lumber yards. [0039] Class VI: Electric and Internal Combustion Engine Tractors (Solid and Pneumatic Tires). Powered industrial trucks in this class are usually sit-down rider tow tractors used for pulling loads (rather than lifting). They can be used in both indoor and outdoor environments. [0040] Class VII: Rough Terrain Forklift Trucks (Pneumatic Tires). Powered industrial trucks in this class are typically used in construction, logging, and other rough terrain applications. They have large, tractor-style tires for navigating over difficult terrain, and are frequently used for lifting and transporting heavy loads.

[0041] FIGS. 6-12 of this application depict examples of Class I to Class VII powered industrial trucks according to the United States Department of Labor Occupational Safety and Health Administration (OSHA).

[0042] As indicated herein, the present application relates primarily to Class II powered industrial trucks, i.e., narrow aisle forklifts or trucks, including reach trucks, orders pickers, and very narrow aisle forklifts, also referred to as turret trucks, and, more specifically, to wheel assemblies and outriggers used therein.

[0043] As referred to herein, disclosures of ranges are, unless specified otherwise, inclusive of endpoints and include all distinct values and further divided ranges within the entire range. Thus, for example, a range of from A to B or from about A to about B is inclusive of A and of B. Disclosure of values and ranges of values for specific parameters (such as amounts, weight percentages, etc.) are not exclusive of other values and ranges of values useful herein. It is envisioned that two or more specific exemplified values for a given parameter may define endpoints for a range of values that may be claimed for the parameter. For example, if Parameter X is exemplified herein to have value A and also exemplified to have value Z, it is envisioned that Parameter X may have a range of values from about A to about Z. Similarly, it is envisioned that disclosure of two or more ranges of values for a parameter (whether such ranges are nested, overlapping or distinct) subsume all possible combination of ranges for the value that might be claimed using endpoints of the disclosed ranges. For example, if Parameter X is exemplified herein to have values in the range of 1-10, or 2-9, or 3-8, it is also envisioned that Parameter X may have other ranges of values including 1-9, 1-8, 1-3, 1-2, 2-10, 2-8, 2-3, 3-10, 3-9, and so on.

[0044] FIG. 1 shows Class II material handling vehicle 1, namely, a reach truck. Vehicle 1 has body 2 supporting mast 3, for raising and lowering forks 4. Drive wheel 5 is positioned at the rear of body 2, along with a caster wheel (not shown). Vehicle 1 is provided with outriggers 6 and 7, which extend from the front of body 2, on either side of forks 4.

[0045] Each of outriggers 6 and 7 has first axle 8, with a plurality of wheels mounted thereon, and second axle 9, with a plurality of wheels mounted thereon. First axle 8 and second axle 9 are arranged in tandem, with the axles aligned perpendicular to the longitudinal extend of the outrigger, which in this case is the ordinary direction of travel of vehicle 1.

[0046] Referring to FIG. 2, wheel assembly 10 has first axle 11, with wheels 12a, 12b and 12c mounted thereon. Wheels 12a, 12b and 12c rotate independently of each other. Wheel assembly 10 is provided with second axle 13, with wheels 14a, 14b and 14c mounted thereon, which also rotate independently of each other. Axles 11 and 13 each have one end supported by bracket 15, and the axles each have an opposite end supported by bracket 16. Brackets 15 and 16 are joined together by brace 17, which spans the wheels 12a-c and 14a-c, and maintains brackets in the desired orientation, that is, parallel to each other and perpendicular to axles 11 and 13. Bracket 15, bracket 16 and brace 17 may be fashioned from a unitary plate of metal, which has been bent into the desired orientation.

[0047] Wheel assembly 10 is provided with mounting hardware, for pivotally engaging an outrigger of a material handling vehicle. In the embodiment illustrated in FIG. 2, bracket 15 is provided with projection 18, and bracket 16 is provided with projection 19. Accordingly, an outrigger of a material handling vehicle can be configured to accommodate projections 18 and 19, in a way that will allow wheel assembly 10 to pivot on an imaginary axis extending between projections 18 and 19. In this way, the wheel assembly forms a complete module, which can be mounted on the outrigger of a material handling vehicle.

[0048] FIG. 3 shows another embodiment of the wheel assembly of the present invention.

[0049] Wheel assembly 20 has first axle 21, with wheels 22a, 22b and 22c mounted thereon. Wheels 22a, 22b and 22c rotate independently of each other. Wheel assembly 20 is provided with second axle 23, with wheels 24a, 24b and 24c mounted thereon, which also rotate independently of each other. Axles 21 and 23 each have one end supported by bracket 25 and the axles each have an opposite end supported by bracket 26. Brackets 25 and 26 are joined together by shaft 27, which maintains the brackets in parallel relationship, perpendicular to the axles. When wheel assembly 20 is mounted on an outrigger, wheel assembly 20 pivots on an axis extending through shaft 27. Thus, wheel assembly 20 forms a complete module, which can be mounted on the outrigger of a material handling vehicle.

[0050] It has been found to be advantageous to offset the axis on which the wheel assembly pivots from the first and second axles. In other words, the pivot point, first axle and second axle may not necessarily be in a straight line. For example, if the pivot point of the wheel assembly is taken as the vertex, then a ray extending from the vertex to the first axle forms one arm of an angle and a ray extending from the vertex to the second axle fom1s a second am1 of an angle.

[0051] The angle between the pivot point, first axle and second axle may range from 20 to 180, preferably greater than 30 and less than 180, in particular, from 35 to 170, and more particularly, from 40 to 150. Referring to FIG. 3, the angle is show as 8, which is formed by arm A, vertex B and arm C. In an embodiment of the present application, the pivot point is located less than one wheel radius above a line (or plane) connecting the first and second axles, to maintain stability when the wheel, wheel assembly, outrigger, or truck strikes an object. In an alternative embodiment, a negative angle may be provided, i.e., the center pivot may be located below the centerline of one or more of the axles with respect to the ground or floor. Such an arrangement would provide extra stability with respect to circumstances in which the wheels, wheel assembly, outrigger, or truck struck an object. In the alternative embodiment, the wheel assembly would create a level to return the wheel assembly to the desired orientation.

[0052] Referring to FIG. 4, a cross-sectional view of a wheel assembly of the present invention is shown. Wheel assembly 30 has first axle 31, with wheels 32a, 32b and 32c mounted thereon, and which rotate independently of each other. Each of the wheels may be comprised of outer tire 33, mounted on rim 34. Bearings 35 are provided between rim 34 and axle 31, as is known in the art. Wheel assembly 30 is further provided with second axle 36, with wheels 37a, 37b and 37c, which rotate independently of each other. Wheels 37a-c may be comprised of the same tire, rim and bearings arrangement, as illustrated with regard to wheel 32a. Wheel assembly has projections 38 and 39 for pivotally mounting the wheel assembly on the outrigger of a material handling vehicle, as described with regard to the embodiment of the invention disclosed in FIG. 3.

[0053] FIG. 4 illustrates the relationship between the distance from the first axle to the second axle, shown as X, and the aggregate width of the wheels on an axle, shown as Y. The ratio of X divided by Y may be between 0.5 and 1.3, in particular, between 0.5 and 1.2, more particularly, between 0.6 and 1.1.

[0054] FIG. 5 is a side view of the wheel assembly of FIG. 3, which is also applicable to the wheel assembly illustrated in FIG. 2. Referring to FIGS. 4 and 5, wheel assembly 20 has first axle 21, wheels 22a-22c, second axle 23 and wheels 24a-24c. Axles 21 and 23 are supported by brackets 25 and 26. Shaft 27 is the pivot point of wheel assembly 20. Segment D is the distance between the axis of axle 21 to the axis of shaft 27. Segment E is the distance between the axis of axle 23 to the axis of shaft 27. The ratio of segment D to segment E may range from 1:4 to 4:1, in particular, from 1:2.3 to 2.3:1, more particularly, from 1:1.5 to 1.5:1.

[0055] FIG. 6 includes several examples of Class I powered industrial trucks. These examples are enumerated as follows: (A) Code 1: Counterbalanced Rider Type, Stand Up. (B) Code 4: Three Wheel Electric Trucks, Sit Down. (C) Code 5: Counterbalanced Rider, Cushion Tires, Sit Down. (D) Code 6: Counterbalanced Rider, Pneumatic or Either Type Tire, Sit Down.

[0056] FIG. 7 includes several examples of Class II powered industrial trucks. These examples are enumerated as follows: (A) Code 1: High Lift Straddle. (B) Code 2: Order Picker. (C) Code 3: Reach Type Outrigger. (D) Code 4: Side Loaders: Platforms. (E) Code 4: Side Loaders: High Lift Pallet. (F) Code 4: Turret Trucks. (G) Code 6: Low Lift Platform. (H) Code 6: Low Lift Pallet.

[0057] FIG. 8 includes several examples of Class III powered industrial trucks. These examples are enumerated as follows: (A) Code 1: Low Lift Platform. (B) Code 2: Low Lift Walkie Pallet. (C) Code 3: Tractors. (D) Code 4: Low Lift Walkie/Center Control. (E) Code 5: Reach Type Outrigger. (F) Code 6: High Lift Straddle. (G) Code 6: Single Face Pallet. (H) Code 6: High Lift Platform. (I) Code 7: High Lift Counterbalanced. (J) Code 8: Low Lift Walkie/Rider Pallet and End Control.

[0058] FIG. 9 includes an example of a Class IV powered industrial truck. These example is enumerated as follows: (A) Code 3: Fork, Counterbalanced (Cushion Tire).

[0059] FIG. 10 includes an example of a Class V powered industrial truck. These example is enumerated as follows: (A) Code 4: Fork, Counterbalanced (Pneumatic Tire).

[0060] FIG. 11 includes an example of a Class VI powered industrial truck. These example is enumerated as follows: (A) Code 1: Sit-Down Rider (Draw Bar Pull Over 999 lbs.).

[0061] FIG. 12 includes several examples of Class VII powered industrial trucks. These examples are enumerated as follows: (A) Vertical mast type. (B) Variable reach type. (C) Truck/trailer mounted.

[0062] The present invention has been described in relation to a material handling vehicle having outriggers or legs, extending from the body of the vehicle, for example, laterally in the direction of the forks or platform that is raised to retrieve pallets and goods stored in a warehouse. A pair of the subject wheel assemblies may also be employed to replace a set of load wheels positioned in the back or front of the body of the vehicle, that is, directly under the body, rather than in an outrigger.

[0063] There are, of course, many alternative embodiments and modifications of the invention intended to be included in the scope of the claims.

FURTHER EMBODIMENTS

[0064] A-1. A wheel assembly for an outrigger of a material handling vehicle, comprising: [0065] a first axle, a first wheel mounted on the first axle and a second wheel mounted on the first axle, whereby the first wheel and the second wheel rotate independently; [0066] a second axle, a first wheel mounted on the second axle and a second wheel mounted on the second axle, whereby the first wheel and the second wheel rotate independently; [0067] wherein the first axle and the second axle are mounted on the outrigger, in tandem.
A-2. The wheel assembly of A-1, wherein a distance between the first axle and the second axle has a value of X, and a distance between an outside of the first wheel and an outside of the second wheel on the first axle has a value of Y, and X/Y is between 0.5 and 1.3.
A-3. The wheel assembly of A-1 to A-2, wherein the first axle has a first end and a second end and the second axle has a first end and a second end, and the wheel assembly further comprises (i) a first bracket engaging the first end of the first axle and the first end of the second axle, and (ii) a second bracket engaging the second end of the first axle and the second end of the second axle, whereby the first bracket and the second bracket are parallel to each other and perpendicular to the first axle and second axle, and whereby the first and second brackets can be pivotally mounted on the outrigger.
A-4. The wheel assembly of A-1 to A-3, further comprising a shaft having a first end engaging the first bracket and a second end engaging the second bracket, and the wheel assembly can be mounted on the outrigger, whereby the wheel assembly pivots around the shaft.
A-5. The wheel assembly of A-1 to A-4, wherein the first bracket has a first outwardly facing projection and the second bracket has a second outwardly facing projection and the first projection and the second projection can engage the outrigger, whereby the wheel assembly pivots around the first and second projections.
A-6. The wheel assembly of A-1 to A-5, whereby the wheel assembly pivots at a point, and the first axle and the second axle are at an angle of 30 to 180 relative to the pivot point.
A-7. The wheel assembly of A-1 to A-6, further comprising a third wheel mounted on the first axle, and the third wheel rotates independently of the first and second wheels of the first axle.
A-8. The wheel assembly of A-1 to A-7, further comprising a third wheel mounted on the second axle, and the third wheel rotates independently of the first and second wheels on the second axle.
A-9. The wheel assembly of A-1 to A-8, wherein a distance between the first axle and the second axle has a value of X, and a distance between an outside of the first wheel and an outside of the third wheel on the first axle has a value of Y, and X/Y is between 0.5 and 1.3.
A-10. The wheel assembly of A-1 to A-9, wherein the first axle has a first end and a second end and the second axle has a first end and a second end, and the wheel assembly further comprises (i) a first bracket engaging the first end of the first axle and the first end of the second axle, and (ii) a second bracket engaging the second end of the first axle and the second end of the second axle, whereby the first bracket and the second bracket are parallel to each other and perpendicular to the first axle and second axle, and whereby the first and second brackets can be pivotally mounted on the outrigger.

[0068] The foregoing description of preferred embodiments has been presented for purposes of illustration and description only. It is not intended to be exhaustive or to limit the application to the precise form disclosed, and modifications and variations are possible and/or would be apparent in light of the above teachings or may be acquired from practice of the application. The embodiments were chosen and described in order to explain the principles of the application and its practical application to enable one skilled in the art to utilize the application in various embodiments and with various modifications as are suited to the particular use contemplated. It is intended that the scope of the application be defined by the claims appended hereto and that the claims encompass all embodiments of the application, including the disclosed embodiments and their equivalents.