Patent Publication Number: US-8985620-B2

Title: Steerable wheelbarrow

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application is related to and claims priority to prior U.S. patent application Ser. No. 13/456,000, entitled “STEERABLE WHEELBARROW”, filed Apr. 25, 2012 which application is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Technical Field 
     This invention relates to a wheelbarrow with a pivoting axle that can be easily changed to a stationary or almost stationary axle when desired. 
     2. Background Art 
     Wheelbarrows have been around for centuries. There are reports of wheelbarrows being used in China during the second century A.D. Wheelbarrows also appear to have existed in Ancient Greece and possibly Rome. 
     Typically a wheelbarrow consists of a tray or container into which heavy loads are placed. The tray is supported by a single wheel and has two handles which can be used to propel and steer the wheelbarrow. 
     These traditional wheelbarrows are often difficult to steer or maneuver, particularly over rough ground. Adding a heavy load to one of these wheelbarrows makes it even more difficult to steer. Often, a wheelbarrow may tip over when the user is trying to turn it. If the wheelbarrow is filled with a substance such as a liquid, spilling may occur when the wheelbarrow is pushed over rough ground. 
     More modern wheelbarrows often have two wheels positioned towards the front of the tray. Using two wheels helps to make the wheelbarrow more stable, though rough terrain is still an issue. However, using two wheels does not make the wheelbarrow easier to steer. In fact, the addition of the second wheel may make the wheelbarrow even harder to steer. 
     In the past, people have attempted to make wheelbarrows more maneuverable or more stable. The problem is that they never managed to create a wheelbarrow that was both more maneuverable and more stable. The prior art contains many examples such as U.S. Pat. No. 2,492,157 which has a steering mechanism that turns the wheel of the wheelbarrow when a user bends the handle at a hinge. U.S. Pat. No. 5,924,708 is similar in that movement of the wheel or wheels of the wheelbarrow is controlled by the user turning a handle. These wheelbarrows, though more maneuverable, are still unstable on rough terrain. 
     U.S. Pat. No. 7,934,728 describes a wheelbarrow that has a horizontal pivot point around which the axle rotates in order to compensate for rough terrain. This invention, though it may be more stable, is as hard or harder to steer as a standard wheelbarrow. 
     Accordingly, what is needed is a wheelbarrow that is stable enough to allow the user to move spillable items while also being easy to steer or maneuver. 
     DISCLOSURE OF THE INVENTION 
     The steerable wheelbarrow, as disclosed hereafter in this application, is easily maneuverable while also being stable. The axle of the steerable wheelbarrow may also be reversed in order to change the wheelbarrow from a steerable wheelbarrow to a wheelbarrow with a substantially stationary axle. 
     In particular embodiments, a wheelbarrow may include a tray with two handles coupled to it. At least one leg may be coupled to the handles. A mount may also be coupled to the handles. A pivot may be coupled to the mount, wherein the pivot may be coupled to the mount at an angle between vertical and horizontal. An offset sleeve may be rotatably coupled to the pivot. An axle may be coupled to the offset sleeve. At least one wheel may be coupled to the axle. A pivot support may be coupled to the pivot, wherein the pivot support may also be coupled to the mount. When the offset sleeve is positioned with the axle coupled to a distal side of the offset sleeve, the axle rotates with respect to the pivot; and when the offset sleeve is positioned with the axle coupled to a proximal side of the offset sleeve, the axle&#39;s rotation is limited with respect to the pivot. 
     Alternate embodiments of a wheelbarrow may include a tray with a front end and a user end. Two braces may be coupled to the tray at a location near the front end of the tray. Two handles may each be coupled to the tray at a location near the user end of the tray and each handle may also be coupled to one of the two braces. Two legs may each be coupled to one of the two handles. A mount may be coupled to both of the two handles at a location near the front end of the tray. A pivot may be coupled to the mount wherein the pivot further includes at least two ends and is coupled to the mount at a location near one of the at least two ends of the pivot. The pivot may be coupled to the mount at an angle approximately 30 degrees less than vertical. An offset sleeve may be rotatably coupled to the pivot. An axle may be coupled to the offset sleeve wherein the axle has two ends. Two wheels may be coupled to the axle at a location near each of the two ends of the axle. A pivot support may be coupled to the pivot wherein the pivot support is coupled to the pivot at a location near the one of the at least two ends of the pivot that is not coupled to the mount. The pivot support is also coupled to the mount. 
     Embodiments of an axle assembly as used in a wheelbarrow may include a mount. A pivot further includes a first and a second end and wherein the first end may be coupled to the mount. The pivot may be coupled to the mount at an angle between vertical and horizontal. An offset sleeve may be rotatably coupled to the pivot at a location between the first and the second end of the pivot. An axle may be fixedly coupled to an outer diameter of the offset sleeve. A pivot support may be coupled to the second end of the pivot and to the mount. 
     The foregoing and other features and advantages of the steerable wheelbarrow will be apparent to those of ordinary skill in the art from the following more particular description of the invention and the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will hereinafter be described in conjunction with the appended drawings where like designations denote like elements, and: 
         FIG. 1  is an isometric view of a steerable wheelbarrow; 
         FIG. 2  is an exploded view of a steerable wheelbarrow; 
         FIG. 3  is a partially exploded side view of a steerable wheelbarrow; 
         FIG. 4  is a bottom view of a steerable wheelbarrow; 
         FIG. 5  is an isometric view of an axle assembly for use on a steerable wheelbarrow; 
         FIG. 6  is a bottom view of an axle assembly for use on a steerable wheelbarrow; 
         FIG. 7  is a top view of an axle assembly for use on a steerable wheelbarrow; 
         FIG. 8  is an exploded view of an axle assembly for use on a steerable wheelbarrow; 
         FIG. 9  is an isometric view of an additional embodiment of a wheelbarrow; 
         FIG. 10  is an exploded view of an additional embodiment of a wheelbarrow; 
         FIG. 11  is an exploded view of an axle assembly for use on an alternative embodiment of a wheelbarrow; 
         FIG. 12  is an isometric view of an axle assembly with an axle offset in a distal direction for use on an additional embodiment of a wheelbarrow; and 
         FIG. 13  is an isometric view of an axle assembly with an axle offset in a proximal direction for use on an additional embodiment of a wheelbarrow. 
     
    
    
     DESCRIPTION OF THE INVENTION 
     As discussed above, embodiments of the present invention relate to a steerable wheelbarrow. In particular, a wheelbarrow which allows a user to more easily maneuver or steer the wheelbarrow and which allows the wheels on the wheelbarrow to move up and down in order to compensate for rough terrain in order to prevent the contents of the wheelbarrow from spilling. Additional embodiments of the present invention, include an axle which may be reversed in order to allow the user to change the wheelbarrow from a steerable wheelbarrow to a wheelbarrow with a fixed or substantially fixed axle. Generally, a steerable wheelbarrow comprises a tray, at least two handles, a mount, a pivot, an axle, at least one wheel and a pivot support. 
       FIGS. 1-4  illustrate a steerable wheelbarrow  10 . The steerable wheelbarrow  10  comprises a tray  12 . The tray  12  of the wheelbarrow  10  may be formed from wood, plastic, metal or the like and may be formed in any shape that will contain items carried in the wheelbarrow  10 . Typically a wheelbarrow tray  12  is formed as a kind of bucket which is shallower at one end than the other. The shallow end of the bucket is positioned nearest the user or at the user end of the wheelbarrow  10 . The user end  11  of the wheelbarrow  10  is the end closest to a user when the user is pushing the wheelbarrow  10 . The deeper end of the tray  12  is positioned at a front end  13  of the wheelbarrow  10 . The front end  13  of the wheelbarrow  10  is the end of the wheelbarrow  10  farthest away from the user when the user is pushing the wheelbarrow  10 . 
     A steerable wheelbarrow  10  may also comprise at least one handle  14 . A steerable wheelbarrow  10  will typically have two handles  14  configured similarly to a standard wheelbarrow. The handles  14  on the wheelbarrow  10  extend from the user end  11  of the wheelbarrow  10  to the front end  13  of the wheelbarrow  10 . The handles  14  are coupled to the tray  12  of the wheelbarrow  10 , with the tray  12  coupled towards the front end  13  of the handles  14 . The handles  14  allow the user of the wheelbarrow  10  to lift the wheelbarrow  10  and to maneuver the wheelbarrow  10 . 
     The front of the handles  14  are hooked together by a handle connecter  28 . The handle connector  28  helps to hold the handles  14  in position. The handle connector  28  is typically a strip of metal with two mostly right angles located at each of the ends of the strip of metal. The right angles are coupled around the end of the handles  14  of the wheelbarrow  10  positioned at the front end  13  of the wheelbarrow  10 . 
     Coupled to the bottom of the handles  14  is at least one leg  16 . The legs  16  on a wheelbarrow  10  allow the wheelbarrow to sit with the tray  12  in a relatively level positioned while the user is not pushing the wheelbarrow  10 . Some typical wheelbarrows have one leg  16  which couples to each of the handles  14  on the wheelbarrow. This type of leg  16  is formed from a strip of metal bent into the shape of a rectangle with one missing side. The open side is the side that will be coupled to the handles  14  of the wheelbarrow, while the closed side of the rectangle will support the wheelbarrow on the ground. Other typical wheelbarrow legs  16  are formed from two pieces of metal bent into a triangle with a missing side. The open side of the triangle is coupled to the handle  14  of the wheelbarrow. One triangle is coupled to each of the handles  14 . 
     At least one brace  30  may be coupled to the handles  14  of the wheelbarrow. In typical wheelbarrow configurations, two braces  30  are used. Each brace is coupled to one of the handles  14  of the wheelbarrow at a location towards the front end  13  of the wheelbarrow. The braces  30  are then coupled to the underside of the tray  12  of the wheelbarrow. The braces  30  help to support the tray  12 . Braces  30  are typically used on wheelbarrows where the tray  12  is made of plastic. Braces  30  may be formed from straight pieces of metal. 
     All of the components of a wheelbarrow discussed previously may be coupled together using screws, bolts, nails, adhesives, welding, epoxy, fasteners or the like. 
     In a steerable wheelbarrow  10  such as those discussed in this disclosure, a unique axle assembly  50  is coupled to the bottom of the handles  14  towards the front end  13  of the wheelbarrow  10 . The axle assembly  50  is shown as part of the wheelbarrow  10  in  FIGS. 1-4 . The axle assembly  50  is shown separately from the wheelbarrow in  FIGS. 5-8 . 
     The axle assembly  50  as shown in  FIGS. 5-8  may be used to replace the axle on any standard wheelbarrow in order to convert that wheelbarrow to a steerable wheelbarrow  10 . This is done by coupling the axle assembly  50  to the handles  14  on the standard wheelbarrow at a location approximately the same as where the original wheels were located. 
     The axle assembly  50  comprises, includes or contains a mount  18 . This mount  18  is simply a mounting plate that allows the axle assembly  50  to be coupled to the bottom of the wheelbarrow handles  14 . The mount  18  as shown in the figures is a metal plate which may be approximately 3/16 to ¾ of an inch thick, however the mount  18  may be made from any material that is strong enough to prevent the axle assembly  50  from being torn from the bottom of the wheelbarrow  10  when the wheelbarrow is being used. The mount  18  may also be as thick or thin as needed. The mount  18  is shaped like a simple rectangle. Towards the front of the mount  18  is a trapezoidal piece of material  19  which is coupled to the rectangle at an angle. This angle is somewhere between horizontal and vertical, however for preferred arrangements it is likely that the trapezoidal piece of material  19  is coupled to the rectangular piece of material at an angle of approximately 30 degrees below horizontal. 
     Though, for the purpose of this illustration, the pieces of material are rectangular and trapezoidal, they may be formed in any shape desired. 
     Coupled to the sides of the rectangular piece of the mount  18  are two longer rectangular pieces of material. These longer rectangular pieces are placed so as to allow the mount  18  to be coupled to the handles  14  of the wheelbarrow  10 . 
     The pieces of the mount  18  may be coupled with adhesives, welding, fasteners or the like. Typically if the mount  18  is formed from metal, the pieces will be coupled by welding. 
     Along the sides of the mount  18  are coupling holes  38  which allow the metal mount  18  to be coupled to the wooden handles  14  of the wheelbarrow  10 . These holes  38  allow couplers  40  to be placed through the mount  18  and into the handles  14 . Typical couplers  40  may include bolts, wood screws, nails or the like. The mount  18  may have as few or as many coupling holes  38  as needed to securely fasten the mount  18  to the wooden handles  14  of the wheelbarrow  10 . 
     Attached to the trapezoidal piece of material  19  on the mount  18  is a pivot  20  and a pivot support  26 . The pivot  20  is a long cylindrical part around which axle  22  of the axle assembly  50  will rotate. The pivot  20  may be formed from a rod, pin or a bolt as illustrated in the attached figures. The pivot  20  may be formed from any cylindrical piece of material about which axle  22  may rotate. 
     The pivot  20  is coupled or connected to the mount  18  at the angled trapezoidal piece  19 . This positions the pivot  20  at an angle between vertical and horizontal. A typical configuration may have the pivot  20  located at an approximately 30 degree angle less than vertical. Often vertical may be measured as 90 degrees from the plane in which the handles  14  lie. However, vertical may also simply be perpendicular to the ground. This angle allows the wheels on the end of the axle to pivot forward and backward for steering and up and down for stability. 
     The pivot support  26  is coupled to a first end of the pivot  20  at the same location that the pivot  20  is coupled to the mount  18 . The pivot support  26  is then also coupled to a second end of the pivot  20 . The pivot support  26  then continues to where it is coupled to the rectangular section of the mount  18 . The pivot support  26  provides stability and support to the pivot  20 . The pivot support  26  may be formed from a strip of metal or other strong material. This strip of metal is approximately an inch to two inches in width and may be 3/16 to ⅛ an inch in thickness in this embodiment. In other embodiments, the pivot support  26  may be formed from other shapes, sizes and types of material. The pivot support  26  may be formed in a rounded shape such as the pivot support  26  illustrated in  FIGS. 1-4  or it may be formed with square angles such as the pivot support  26  illustrated in  FIGS. 5-8 . 
     The pivot support  26  and mount  18  may be coupled together by adhesives, welding or the like. The pivot  20  is typically coupled to the mount  18  and pivot support  26  by simply inserting the pivot  20  through pivot holes  54  drilled in the mount  18  and pivot support  26 . After inserting pivot  20  through pivot holes  54  and axle  22 , pivot opening  60 , the end of the pivot  20  then has a pivot nut  56  placed on it, in order to hold the pivot  20  in place. The pivot nut  56  is simply a nut that fits on the pivot  20 . In alternate embodiments, the mount  18  may have a threaded opening into which the pivot  20  is inserted and then the pivot nut  56  is not used. 
     An axle  22  pivots around the pivot  20 . The axle  22  may simply be a standard wheelbarrow axle or the like. It may be cylindrical or rectangular with cylindrical ends. The axle may simply be a long straight axle  22  or it may be horseshoe or other shapes. The center of the axle  22  contains a pivot opening  60 . The pivot opening  60  is simply an opening through which the pivot  20  is placed. The pivot opening  60  may be formed by drilling a hole through the center of the axle  22  or else a bushing  58  may be inserted through the center of the axle  22  and then the bushing  58  is affixed to the axle  22 . 
     If a bushing  58  is used, the bushing  58  may extend beyond the width of the axle  22  in order to position the axle  22  along the pivot  20 . If a bushing  58  is not used, a spacer  36  may be placed along the pivot  20  in order to position the axle  22  appropriately. The spacer  36  may be coupled to the pivot support  26  or it may be simply placed around the pivot  20 . Washers  34  may also be used for additional aid in appropriately positioning the axle  22  along the pivot  20 . 
     At each end of the axle  22 , a wheel  24  is placed on the axle  22 . The wheels  24  rotate freely about the axle  22 . In other configurations, one wheel  24  only may be used. 
     The wheels  24  are held on the axle  22  by wheel nuts  32  which are placed on the axle  22  after the wheels  24 . Wheel nuts  32  are typically just standard nuts, pins, caps or other devices that may be used to hold a wheel  24  on an axle  22 . A wheel stop  21  may be attached to each end of the axle  22 , prior to putting the wheels  24  on the axle  22 . The wheel stops  21  prevent the wheel  24  from sliding towards the center of the axle  22 . A wheel stop  21  may be any device that would keep the wheel  24  from sliding further on the axle  22 . In the FIGs, the wheel stops  21  are large washers which are welded in the proper place on the axle  22 . 
     In order to prevent the axle  22  from rotating in a complete circle around the pivot  20 , which would make using the wheelbarrow  10  difficult, stops may be placed on the mount  18  in order to prevent the axle  22  from rotating more than a predetermined amount. In  FIGS. 1-4 , the stop is formed by placing a stop coupler  42  through a stop hole  46 . The stop coupler  42  may be simply formed from a long screw or bolt. The stop hole  46  is typically the hole on the mount  18  which is positioned closest to the user end of the wheelbarrow. The stop coupler  42  is placed through the stop hole  46  and then the stop coupler  42  is held in place with a nut  44 . The stops may also be adjustable in order to allow the user to determine at what point they would like the axle  22  to stop rotating around the pivot  20 . The stops may be adjustable by providing multiple stop holes  46  through which the stop coupler  42  could be placed, as shown in  FIG. 4 . In order to adjust the location of the stops, the user would move the stop coupler  42  from one stop hole  46  to another stop hole  46 . The stop holes  46  could also be shaped like extended ellipticals in order to provide multiple locations at which the stop couplers  42  could be fastened. 
     In the embodiment of axle assembly  50  illustrated in  FIGS. 5-8 , a stop  52  is coupled to the mount  18  in a position which prevents the axle  22  from rotating around the pivot  20  more than a desired distance. The stop  52  illustrated in these figures is a nut welded to the mount  18 . This stop  52 , however, could be formed in any configuration or with any material desired. 
     In alternate embodiments, a steerable wheelbarrow  10  may be configured using one wheel instead of two. In this configuration, the axle may be formed so as to suspend one wheel below the pivot. This would allow the one wheel to pivot to allow the wheelbarrow to be more maneuverable. 
     In still other embodiments, the angle of the position of the pivot of the steerable wheelbarrow  10  may be adjustable in order to allow the user to determine which angle is best suited to their needs. 
     In some embodiments of a steerable wheelbarrow, the pivot support may also act as a pivot stop to prevent the axle from rotating in a complete circle. 
     Additionally, in alternate embodiments, the at least one wheel  24  may be replaced with at least one ski in order to allow the steerable wheelbarrow  10  to be used on snow or ice. 
       FIGS. 9-13  illustrate an additional embodiment of a wheelbarrow  70 . The axle assembly  78  of wheelbarrow  70  includes an offset sleeve  72 . The offset sleeve  72  is a cylindrical tube configured to receive pivot  20 . The offset sleeve  72  may be formed in any shape or size desired, provided the shape and size allow the pivot  20  to rotate within the offset sleeve  72 . The offset sleeve  72  is placed around the pivot  20  and is then coupled to the axle  22 . The offset sleeve  72  puts the axle  22  in a position to one side or the other, either the distal side or the proximal side, of the pivot  20  rather than centered on pivot  20  as in the other embodiments. 
     The axle  22  is coupled to the outside diameter of the offset sleeve  72  in this embodiment. The axle  22  may be coupled to the offset sleeve  72  permanently or removably. The axle  22  may be welded, bolted, glued, epoxied or the like to the offset sleeve  72 . 
     The axle  22  is offset in either a distal direction  74  ( FIG. 12 ) or a proximal direction  76  ( FIG. 13 ) by the offset sleeve  72 . The distal direction  74  is the direction towards the front end of the wheelbarrow  70 . The distal direction  74  is also the direction away from the user. The proximal direction  76  is the direction towards the user. 
     If the axle  22  is offset in the distal direction  74 , the axle  22  is allowed to pivot freely around the pivot  20 . The axle  22  will pivot until the axle  22  comes into contact with pivot stop  52 . In this configuration, the wheelbarrow  70  is a steerable wheelbarrow as described previously. 
     If the axle  22  is offset in the proximal direction  76 , the axle&#39;s  22  rotation is limited and the axle  22  is held in a stationary or almost stationary position. The axle  22  is held between the pivot  20  and the pivot stops  52 . In this configuration, the axle  22  is fixed in position, in other words, axle  22 &#39;s rotation is limited with respect to pivot  20 , which allows the user to carry loads which would be difficult with a pivoting axle  22 . In many instances the axle will have zero rotation in this position, however, it is possible that the axle will rotate less than 10 degrees in either direction. 
     In order to switch axle  22  from a distal offset as illustrated in  FIG. 12  to a proximal offset as illustrated in  FIG. 13 , the user removes pivot  20  which may be a bolt, a screw or the like. Once pivot  20  is removed, the user rotates axle  22  so that offset sleeve  72  is either on the proximal side  76  or the distal side  74 . Once the offset sleeve  72  is in position, the user inserts pivot  20  through pivot support  26 , through offset sleeve  72 , through spacer  36 , if desired, and into mount  18 . Once the pivot  20  is secured, the user may operate the wheelbarrow  70 . 
     If the user desires to switch the axle  22  back from a fixed to a pivoting axle or vice versa, the user simple repeats the above process. In this way, the user may use the same wheelbarrow  70  for many different types of loads. 
       FIG. 11  illustrates an alternative additional embodiment of wheelbarrow  70 . In this figure, pivot  20  is a pin which slides through pivot support  26 , offset sleeve  72 , spacer  36 , if desired, and into mount  18 . Pivot  20  is held in place by retaining wire  82 . Retaining wire  82  is a wire formed into a partial square. Retaining wire  82  may be formed from wire, metal strips, plastic or any other desired material which performs the purpose of securing pivot  20  into position. Retaining wire  82  may be formed from any thickness or type of wire, if wire is used. Retaining wire  82  may also be formed in any shape desired such as a partial circle, partial, rectangle or the like. 
     One end of retaining wire  82  is rotatably coupled to one end of pivot  20 . The other end of retaining wire  82  has an opening through which the other end of pivot  20  may be inserted. When the user is removing pivot  20  from the wheelbarrow  70  in order to reverse the axle  22 , the end of retaining wire  82  which has the opening is removed from the end of the pivot  20 . The retaining wire  82  is then rotated around the end of the retaining wire  82  which is rotatably coupled to the pivot  20 . The pivot  20  can then be removed from the offset sleeve  72  so that the position of the axle  22  may be reversed. Once the axle  22  is in the desired position, the pivot  20  may be reinserted through the pivot support  26 , offset sleeve  72 , spacer  36 , if desired, and into mount  18 . Then the retaining wire  82  is rotated so that the open end of the retaining wire  82  may be placed over the end of the pivot  20 , thereby securing the pivot  20  into position. 
     Accordingly, for the exemplary purposes of this disclosure, the components defining any embodiment of the invention may be formed as one piece if it is possible for the components to still serve their function. The components may also be composed of any of many different types of materials or combinations thereof that can readily be formed into shaped objects provided that the components selected are consistent with the intended mechanical operation of the invention. For example, the components may be formed of rubbers (synthetic and/or natural), glasses, composites such as fiberglass, carbon-fiber and/or other like materials, polymers such as plastic, polycarbonate, PVC plastic, ABS plastic, polystyrene, polypropylene, acrylic, nylon, phenolic, any combination thereof, and/or other like materials, metals, such as zinc, magnesium, titanium, copper, iron, steel, stainless steel, any combination thereof, and/or other like materials, alloys, such as aluminum, and/or other like materials, any other suitable material, and/or any combination thereof. 
     The embodiments and examples set forth herein were presented in order to best explain the present invention and its practical applications and to thereby enable those of ordinary skill in the art to make and use the invention. However, those of ordinary skill in the art will recognize that the foregoing description and examples have been presented for the purposes of illustration and example only. The description as set forth is not intended to be exhaustive or to limit the invention to the precise form disclosed. Many modifications and variations are possible in light of the teachings above without departing from the spirit and scope of the forthcoming claims. Accordingly, any components of the present invention indicated in the drawings or herein are given as an example of possible components and not as a limitation.