WO2009066111A2

WO2009066111A2 - Wheelbarrow

Info

Publication number: WO2009066111A2
Application number: PCT/GB2008/051098
Authority: WO
Inventors: Toby Palmer
Original assignee: Toby Palmer
Priority date: 2007-11-21
Filing date: 2008-11-21
Publication date: 2009-05-28
Also published as: WO2009066111A3; EP2222528A2; GB0722800D0

Abstract

A wheelbarrow (2) including a frame (4) with three wheels(10, 50), a hopper (6) and hopper tipping arrangement. The hopper (6) is pivotally mounted to the frame (4) at a front pivot and a handle (34) pivotally moveable about a rear pivot mounted to the frame. The hopper tipping arrangement includes a tipping member (45) extending downwardly and forwardly from the front pivot(8). The handle (34) is pivotally secured to a link member(13), which member (13) is pivotally connected to the tipping member (45). The handle (34) is moveable about the rear pivot (40) such that downwards movement thereof actuates the hopper tipping arrangement, causing the hopper (6) to pivot about the front pivot (8) from a load carrying position to a load discharging position.

Description

WHEELBARROW

The present invention relates to a wheelbarrow and to a tipping assembly for use with a wheel barrow.

It has been demonstrated over time that the wheelbarrow is an extremely reliable and useful tool, making the life of its user more simple and convenient in transporting loads. This has been proven especially in industry and agriculture, as well as for general home and garden maintenance.

However, the design of the conventional wheelbarrow has remained unchanged for many years and it no longer meets the needs of all of its potential users. Most conventional wheelbarrows comprise a hopper rigidly mounted on a frame, the frame being provided with a wheel at the front end and two ground engaging supports and two handles at the rear end in order to move the wheelbarrow and a load contained within the hopper a user grips and lifts the handles such that the ground engaging supports are lifted clear of the ground. The user then pushes the handles and the wheelbarrow travels on the wheel in the direction of the push. Steering of the wheelbarrow is effected by pushing the handles to the side in order to point the wheel in the desired direction of travel. When it is desired to unload the wheelbarrow the user must push the handles up such that the hopper pivots about the wheel and the load is discharged over the front of the wheelbarrow.

It can require a great deal up strength to lift, carry and unload a conventional wheelbarrow and not all potential users have the necessary strength. Furthermore, prolonged periods of use can lead to health problems, such as back ache and other complaints. In the modern marketplace increasing numbers of people are demanding more user-friendly products, and, as such, there is a growing market for such products. In addition, more stringent health and safety rules mean that employers are more concerned with avoiding injury to their employees. There are many people who are willing to do such work, but are not physically able to lift, push and dump a load carried in a standard wheelbarrow.

It is an object of the present invention to overcome some of the problems of the prior art, or at least to provide an alternative to the conventional wheelbarrow design.

A first aspect of the invention provides a wheelbarrow comprising a frame, a hopper, a handle member and hopper tipping means operable to move the hopper from a load carrying position to a load discharging position, the hopper being pivotally mounted to the frame at a front pivot point, the handle member having first and second ends and being pivotally mounted between its ends to a rear pivot point of the frame, the hopper tipping means including a tipping member and a link member, the tipping member being secured to and extending downwardly and forwardly from a front portion of the hopper, the link member being pivotally secured at or adjacent one of its ends to the first end of the handle member and at or adjacent the other of its ends to a front portion of the tipping member, wherein a downward movement, in use, of the second end of the handle member causes the first end to push a rearward underside portion of the hopper upwardly from the load carrying position and to pull the tipping member to move the hopper into the load discharging position.

The wheelbarrow has the advantage in that it does not require a user to lift the hopper and pivot it about the front wheel in order to discharge a load from the hopper. The hopper tipping means can be operated to move the hopper from a first, load carrying position to a second, load discharging position. Rather than being rigidly fixed to the frame, as is found in prior art wheelbarrows, the hopper is pivotally attached to a front pivot and can pivot from the load carrying position, when the base of the hopper is generally parallel to the frame and the load is retained within the hopper, to the load discharging position, when the base of the hopper is generally perpendicular to the frame and the load is discharged from the hopper.

For the avoidance of doubt, the term "pivotally secured" as used herein refers to the members being substantially secured relative to one another, only being free to pivot but not to slide relative to each other. It will be appreciated by those skilled in the art that the linkage arrangement shown in the drawings, wherein the tipping member extends downwardly and forwardly from a front portion of the hopper, precludes the need for a slideable and pivotable connection between the link member and the handle member.

A second aspect of the invention provides a wheelbarrow comprising a frame with three or more wheels, a hopper and hopper tipping means, the hopper being pivotally mounted to the frame at a front pivot and handle means pivotally moveable about a rear pivot mounted to the frame, wherein the hopper tipping means comprises a tipping member extending downwardly from the front pivot and the handle means is pivotally connected to the tipping member by a link member wherein the handle means being moveable about the rear pivot such that downwards movement of the handle means actuates the hopper tipping means and causes the hopper to pivot about the front pivot from a load carrying position to a load discharging position The first end of the handle member may abut the hopper, in use, to push it upwardly from the load carrying position. The hopper tipping means may exert, in use, a pulling force, e.g. in a rearward direction, in front of the front pivot, for example to cause the hopper to continue to pivot about the front pivot after the pushing action, thereby to discharge its content. The link member may be caused to pull the tipping member by continued actuation of the handle member.

The hopper may advantageously be mounted on a hopper support frame, which frame would be pivotally attached to the front pivot. A load can therefore be discharged from the hopper without the need to lift the frame. The wheelbarrow preferably comprises a hopper locking mechanism to lock the hopper in the first position during normal use. A user must then unlock the hopper before attempting to discharge the load.

The wheelbarrow may comprise three or more wheels, for example two front wheels and a centrally mounted rear wheel. The front wheels may be mounted on a front axle attached to a front end of the frame and/or the rear wheel may be centrally located on a rear axle attached to a rear end of the frame.

Alternatively, the rear wheel may be a 360 swivel castor. This allows for on the spot 360 turning which greatly improves the manoeuvrability of the wheelbarrow compared to prior art wheelbarrows. The three wheels help to stabilise the wheelbarrow, both during transportation of a load and during discharge of a load. As discussed above, conventional wheelbarrows tend to have a single wheel located at me front of the frame. When the wheelbarrow is being used to transport a heavy load, particularly on soft or boggy ground, the front wheel tends to dig in, making it very difficult to push. The two front wheels help to spread the load and reduce the possibility of getting stuck. Furthermore, the two front wheels provide a stable base to support the wheelbarrow when the load is being tipped using the tipping mechanism.

The rear axle is preferably pivotally mounted on the frame. This provides an effective steering mechanism which enables a user to maneuver the wheelbarrow easily. The wheelbarrow has a relatively sharp turning circle.

It is preferred that the wheels are pneumatic tyres. Pneumatic tyres make the wheelbarrow easy to use on a variety of terrains, including boggy marsh. The wheelbarrow is preferably provided with a brake system. The brake system may be connected to one or more of the wheels.

In a preferred embodiment of the invention, the tipping means comprises pushing means which acts on the hopper at a location behind the front pivot, e.g. on the base of the hopper, to push the hopper over the front pivot. The pushing means may conveniently be actuated by the handle means. Thereafter, the hopper tipping means may exert a pulling force on the front of the hopper to cause it to pivot about the front pivot. The pulling force preferably acts on the hopper in a rearward direction. The rearward pulling force may act radially about the front pivot, e.g. thereby causing the front end of the hopper to pivot down and around the front pivot. The hopper tipping means may take a variety of forms, so long as it is capable of exerting the pushing and pulling forces. Once the initial pulling force has acted on the hopper the load in the hopper begins to fall under gravity and assists in the tipping action.

The pushing means acts in conjunction with the means which exerts the pulling force, wherein it is preferred that the pushing means acts first. This serves to give the hopper the initial energy to pivot about the front pivot. Once the pivoting has begun then the pulling force takes over and pulls the front of the hopper down and around the front pivot thus, the tipping operation is effectively a two-step process. When the handle means is actuated initially the pushing means acts on the hopper to get it started; this is the first step. Once the hopper is moving the second step begins and the pulling force takes over to complete the discharge.

The handle means may comprise a pair of handles extending rearwardly from the wheelbarrow frame, or it may comprise a generally U-shaped member, with the arms being attached to the frame at the rear pivot. This offers the advantage of providing a central bar, rather like a shopping trolley, which the user may push. The handle means is preferably the handle that is used to push the wheelbarrow, but may also be a separate tipping handle.

The handle means is preferably connected to the tipping member by a link member. The link member may conveniently be pivotally attached to the tipping member and the handle means. The handle means acts as a lever to exert a rearward radial pulling force on me tipping member in response to a downward movement of the handle means. The mechanical advantage provided by the lever system means that a heavy load may be discharged from the hopper with relative ease.

A third aspect of the invention provides a tipping assembly for use in a wheelbarrow, the assembly comprising a support frame, a hopper frame a link member and a handle assembly, the handle assembly being pivotally connected to the support frame by a rear pivot, the hopper frame being pivotally connected to the support frame at a front pivot, the hopper frame comprising an arm extending downwardly and forwardly from the front pivot, the link member being pivotally secured to the handle assembly by a first link pivot located intermediate the front and rear pivots, wherein the link member is pivotally connected to the arm of the hopper assembly by a second link pivot which pivot is moveable from a first position forward of the front pivot in a load carrying position to a second position intermediate the first link pivot and front pivot in a load discharging position.

A fourth aspect of the invention provides a method of discharging a load from a hopper mounted to the aforementioned tipping assembly, wherein the hopper frame rests on the first link pivot in the first position and is rotated about the front pivot by the first link pivot when the handle assembly rotates about the rear pivot to the point where the front pivot and second link pivot are substantially aligned in a vertical plane.

The hopper frame may become separated from the first link pivot by continued rotation of the handle assembly about the rear pivot. The hopper frame may continue to rotate about the front pivot, for example due to the rearward pulling action of the handle assembly on the link member which may cause the hopper to discharge its load.

According to a further aspect of the present invention there is provided a wheelbarrow comprising a frame, a hopper and at least three wheels, wherein two front wheels are mounted at the front of the wheelbarrow and a rear wheel is centrally mounted at the rear of the wheelbarrow.

The three wheels help to stabilise the wheelbarrow, both during transportation of a load and during discharge of a load. As discussed above, conventional wheelbarrows tend to have a single wheel located at the front of the frame. When the wheelbarrow is being used to transport a heavy load, particularly on soft or boggy ground, the front wheel tends to dig in, making it very difficult to push. The two front wheels help to spread the load and reduce the possibility of getting stuck. The provision of three wheels also avoids the need for the user to lift the wheelbarrow in order to transport a load. The user simply needs to push the handles of the wheelbarrow in the manner of a shopping trolley.

The two front wheels are preferably mounted on a front axle attached to a front end of the frame and the rear wheel is mounted on a rear axle attached to a rear end of the frame. The rear axle is preferably pivotally mounted on the frame. This provides a convenient steering mechanism and allows a user to turn relatively sharp corners.

The wheelbarrow preferably further comprises hopper tipping means for moving the hopper from a load carrying position to a load discharge position. The hopper is preferably pivotally mounted to the frame at a front pivot and the hopper tipping means is connected to the hopper at or near the front pivot such that, in use, it is operable to pivot the hopper about the front pivot. Additional features of the hopper tipping means may be as described in relation to the wheelbarrow described in the first aspect of the invention.

For a better understanding of the present invention reference will now be made to the accompanying drawings showing, solely by way of example, an embodiment of the invention and, in which:

Fig. 1 shows a side view of a wheelbarrow according to one aspect of the invention in a first position;

Fig. 2 shows a perspective view of the wheelbarrow support frame according to one aspect of the invention;

Fig. 3 shows a side view of the support frame shown in Fig 2 in a first position;

Fig. 4 shows a side view of support frame during the "pushing" phase of the tipping process;

Fig. 5 shows a side view of the support frame during the "pulling" phase of the tipping process;

Fig 6 shows a perspective view of wheelbarrow shown in Fig 1 ; and

Fig 7 shows an end elevation of the wheelbarrow shown in Fig 1 .

Figs. 1 and 2 show a wheelbarrow 2 in a first, or load carrying, position. The wheelbarrow 2 comprises a frame 4 and a hopper 6 attached to a front end of the frame 4 and a front pivot 8 (shown in Fig 2). The hopper 6 is mounted on a hopper support frame 7 which is pivotally connected to the frame about the front pivot 8. The frame 4 and the hopper support frame 7 are formed from lengths of metal tubing and the frame 4 is arranged such that in the first position the hopper support frame 7 supported by, the frame 4.

The hopper 6 is made of plastics material, or other suitable material, and is of a generally conventional, moulded construction. The shape of the hopper is different to a conventional shape in order to move the centre of mass for the reasons outlined below. The front end of the frame 4 is provided with a pair of front wheels 10, preferably in the form of pneumatic tyres. The front wheels 10 are mounted on a front axle 12, which is connected to a front end of the frame 4 to define the front pivot 8.

A swivel castor 50 is mounted to the rear of the frame 4. This improves the manoeuverability of the wheelbarrow 4 and enables a user to move in forward and rearward directions without turning due to the self correction of the swivel castor 50.

A handle 32 is pivotally mounted at an intermediate point to the rear of the frame 4 at a rear pivot 40. The handle 32 is used to push the wheelbarrow 2 in normal use and may also be used to discharge a load from the hopper 6, as will be described in more detail below. The handle 32 comprises a length of tubular material which is bent to form a pushing handle 38 and has a pair of arms 34 which extend under the hopper 6 and are pivotally mounted to the rear of the frame 4 at the rear pivot 40. The arms 34 are bent such that in the load carrying position a forward portion 35 of the arms (in front of the rear pivot) is located under the hopper 6 and a rear portion of the arms (behind the rear pivot) is bent upwards to provide the pushing handle 38. The arms 34 are connected together by intermediate members 39 and 41 which form the rear pivot 40 and an intermediate pivot 31.

The hopper support frame 7 comprises a length of tubular material which is bent to form a cradle for receiving the hopper 6, shown in Figure 2. The hopper support frame 7 includes an intermediate member 43 which forms pivot 8 and an arm 45 extending downwardly, which forms part of the tipping means 26 described below.

The wheelbarrow 2 is provided with tipping means 26, for moving the hopper 6 about the front pivot 8 between the load carrying position (as shown in Fig. 3) and the load discharging position (as shown in Fig. 5). The front pivot 8 itself is the point about which the hopper 6 pivots but it is not part of the tipping means 26. The tipping means 26 comprises the arm 45 which is securely fixed to the pivot member 43 of the hopper support frame 7, at the front pivot 8, and extends downwardly away from the pivot 8. The end of the arm 45 remote from the hopper 6 is pivotally attached to a first end of link member 13 by pivot 33. A second end of the link member 13 is pivotally connected to the intermediate pivot 31 , formed from intermediate member 41 of the handle 32.

In one class of embodiments, the pivotal connections of link member 13 to the pivots 31 and 33 are loose fitting, in that the connecting tubes of link member 13 have an inner diameter greater than the outer diameter of intermediate member 41 and arm 45 respectively.

As the tipping action begins in fig 4 during the "pushing phase of the tipping process", the space within the loose fittings at 31 and 33 begin to close to the point of contact with 41 and 45. This makes the "pushing phase" complete and so now the link member 13 begins to exert a pulling force that becomes the "pulling phase of the tipping process."

The tipping and discharge actions will now be described by reference to Figs 3, 4 and 5. In Fig. 3 the section of the wheelbarrow frames are in a load carrying position. The position of the intermediate pivot is at point A, the front pivot 8 is at point B and the pivot 33 is at point C. Points A, B and C are relative positions in a horizontal plane. The intermediate member 41 is in contact with the hopper frame 7 at point A.

The centre of mass, designated by reference M is preferably between pivots 40 and 8, to ensure a stable structure when the wheelbarrow moves. More preferably the centre of mass is positioned between points A and B to assist with the discharge action, described below.

Referring now to Fig. 4, this shows the support frame of Fig. 3 in an intermediate discharge position. When it is desired to discharge a load from the hopper 6 the handle 32 is pushed downwards in the direction shown by the arrow 42. This action causes the intermediate member 41 to pivot upwards about rear pivot 40. The upwards movement of the pivot 31 exerts an upward pushing action force on the bottom surface of the hopper 6 which causes it to begin to pivot about the front pivot 8.

This action causes the centre of mass M to move towards point B. The pushing action tips the hopper frame 7, which causes the arm 45 to pivot downwardly about pivot 8, which in turn forces member 13 to move and pivot about both pivots 31 and 33. Thus the pivot point A' moves away from B and C towards B. At the point where the centre of mass M is proximate pivot 8 (but still between A' and B) the pushing action is completed. This position is defined as the intermediate tipping position and represents the first step of the two-part tipping process.

As shown in Fig. 5, continued downward movement on the handle 32 causes an upward and rearward pulling force to be exerted on the link member 13. The link member 13 then exerts a rearward radial pulling force exerted on arm 45, which causes the front of the hopper 6 to pivot down and around the front pivot 8, as shown by the arrow 44.

This action causes first point C" to move from a position in front of point B to a position behind it, and the centre of mass M moves forward of point B, to commence the discharge.

As soon as the initial discharge begins the gravitational force of the load in the hopper 6 begins to assist in the tipping, with the result that very little effort is required to discharge even a heavy load. Testing has revealed the tipping mechanism to be very effective in discharging a load from the hopper 6. The tipping action is very quick and results in the load being "dumped" on the ground directly in from of the wheelbarrow 2, rather than sliding out of the hopper 6 gradually. This stage represents the second step in the two-part tipping process.

In a preferred embodiment, the pivot 33 passes under pivot 8 at a point when the centre of mass in above pivot 8 or proximate to it, so that B, C" and M are substantially aligned in a vertical plane. Such an arrangement reduces the risk of the hopper pivoting forward during discharge in an uncontrolled manner which could force the handle in a downward direction.

The arrangement described above improves the handling characteristics of the wheelbarrow during the discharge action, because a positive downward force is required throughout the tipping action, which is in a controlled manner.

In order to make the wheelbarrow 2 easier to handle, a locking mechanism (not shown) is provided to lock the hopper 6 in position during normal use. When the hopper 6 is locked in position it is not possible to push the handles 32 down. This avoids the situation where a load may be inadvertently discharged.

It will be understood that directional terms such as "inner," "outer," "front," "rear", "top", "upper" and "lower" and "side" and the like serve, where used herein, merely to differentiate components of the present invention from one another; their respective components should not be considered to be limited to those orientations, and other reasonable orientations may be adopted without departing from the scope of the present invention.

Claims

1. A wheelbarrow comprising a frame, a hopper, a handle member and hopper tipping means operable to move the hopper from a load carrying position to a load discharging position, the hopper being pivotally mounted to the frame at a front pivot point, the handle member having first and second ends and being pivotally mounted between its ends to a rear pivot point of the frame, the hopper tipping means including a tipping member and a link member, the tipping member being secured to and extending downwardly and forwardly from a front portion of the hopper, the link member being pivotally secured at or adjacent one of its ends to the first end of the handle member and at or adjacent the other of its ends to a front portion of the tipping member, wherein a downward movement, in use, of the second end of the handle member causes the first end to push a rearward underside portion of the hopper upwardly from the load carrying position and to pull the tipping member to move the hopper into the load discharging position.

2. A wheelbarrow according to claim 1 further comprising three or more wheels.

3. A wheelbarrow comprising a frame with three or more wheels, a hopper and hopper tipping means, the hopper being pivotally mounted to the frame at a front pivot and handle means pivotally moveable about a rear pivot mounted to the frame, wherein the hopper tipping means comprises a tipping member extending downwardly from the front pivot and the handle means is pivotally connected to the tipping member by a link member wherein the handle means being moveable about the rear pivot such that downwards movement of the handle means actuates the hopper tipping means and causes the hopper to pivot about the front pivot from a load carrying position to a load discharging position.

4. A wheelbarrow according to any preceding claim, wherein the first end of the handle member or means abuts the hopper, in use, to push it upwardly from the load carrying position.

5. A wheelbarrow according to any preceding claim, wherein, in use, the hopper tipping means exerts a pulling force in front of the front pivot to cause the hopper to continue to pivot about the front pivot after the or a pushing action, thereby to discharge its content.

6. A wheelbarrow according to claim 5, wherein the pulling force acts in a rearward direction in use.

7. A wheelbarrow as claimed in claim 6, wherein the link member is caused to pull the tipping member by continued actuation of the handle member or means.

8. A wheelbarrow according to any preceding claim, wherein the hopper is mounted on a hopper support frame.

9. A wheelbarrow according to any preceding claim comprising two front wheels and a centrally mounted rear wheel.

10. A wheelbarrow according to claim 9, wherein the front wheels are mounted on a front axle attached to a front end of the frame and the rear wheel is centrally located on a rear axle attached to a rear end of the frame.

1 1. A tipping assembly for use in a wheelbarrow, the assembly comprising a support frame, a hopper frame a link member and a handle assembly, the handle assembly being pivotally connected to the support frame by a rear pivot, the hopper frame being pivotally connected to the support frame at a front pivot, the hopper frame comprising an arm extending downwardly and forwardly from the front pivot, the link member being pivotally secured to the handle assembly by a first link pivot located intermediate the front and rear pivots, wherein the link member is pivotally connected to the arm of the hopper assembly by a second link pivot which pivot is moveable from a first position forward of the front pivot in a load carrying position to a second position intermediate the first link pivot and front pivot in a load discharging position.

12. A method of discharging a load from a hopper mounted to the tipping assembly according to claim 1 1 , wherein the hopper frame rests on the first link pivot in the first position and is rotated about the front pivot by the first link pivot when the handle assembly rotates about the rear pivot to the point where the front pivot and second link pivot are substantially aligned in a vertical plane.

13. A method according to claim 12, wherein the hopper frame becomes separated from the first link pivot by continued rotation of the handle assembly about the rear pivot and wherein the hopper frame continues to rotate about the front pivot due to the rearward pulling action of the handle assembly on the link member to cause the hopper to discharge its load.

14. A wheelbarrow substantially as hereinbefore described and/or as shown in the accompanying drawings.

15. A tipping assembly substantially as hereinbefore described and/or as shown in the accompanying drawings.

16. A method of discharging a load substantially as hereinbefore described and/or as shown in the accompanying drawings.