WO2015163804A1

WO2015163804A1 - A hand truck

Info

Publication number: WO2015163804A1
Application number: PCT/SE2015/050365
Authority: WO
Inventors: Jalil GASKARI
Original assignee: Gaskari Jalil
Priority date: 2014-04-25
Filing date: 2015-03-26
Publication date: 2015-10-29
Also published as: SE539128C2; EP3134307A1; SE1650304A1; EP3134307A4

Abstract

The present invention relates to a hand truck comprising a frame (2), a load platform (1) protruding from the frame having a rear portion (21) and a front portion (20), a first and second wheel (6a, 6b) for supporting the platform, and rotatably connected to a first and second primary axis (x1a, x1b) respectively, and a first and second turning unit to turn the first and second wheel respectively at least 90° in relation to the frame about a first and second secondary axis (x2a, x2b) respectively extending orthogonally to the first and second primary axis respectively. The first and second wheels support the rear portion of the load platform, and the hand truck comprises at least one rotatable third wheel (7; 7a-b) to support the front portion of the platform. The third wheel is smaller than the first and second wheels.

Description

A hand truck

Field of the invention

The present invention relates to a hand truck comprising a frame and a load platform protruding from the frame.

Background of the invention and prior art

A hand truck is used for carrying and transporting a load from one place to another place. Conventional hand trucks comprise a load platform for carrying the load and a frame extending upwardly from the load platform, and wheels spacedly supporting the frame. The frame is provided with handles to enable a user to push the truck and its load. When the truck is in an upright position, the load platform rests on a ground level. After the load platform is positioned under the load, the frame can be pivoted backwards such that the load platform with the load is tilted. The hand truck can now be moved backwards by pulling the frame or forwards by pushing the frame. A turning of the truck is performed by pushing or pulling the frame in a turning direction, while holding the truck tilted backwards.

Turning a conventional hand truck is tedious for the user. There is a risk for dislodging of the weight during the pulling and pushing of the hand truck. Further, because the frame must be tilted backwards to release the load platform from the ground, much space is needed for moving and turning the hand truck.

A solution for improving the turning of a hand truck has been found, whereby the wheels can turn in relation to the frame, such that the hand truck can move back and forth as well as from left to right. Such hand trucks are, for example, known from US6,663,120 and US2006/0061053. The turning of the wheels is performed by removing the weight of the load from the wheels and positioning the load platform on the ground level, and then turning the wheels to another position in relation to the frame. Different turning mechanisms have been developed to accomplish the turning of the wheels. After the wheels have been turned, the load platform can be lifted from the ground level by tilting the frame backwards and moved as described above.

Another problem related to hand trucks is that it difficult to transport elongated goods through a narrow passage, for example, a door opening or a narrow corridor.

US4,435,115 discloses a hand truck for transport of pigs. This hand truck has two loading platforms that extend perpendicular to each other and is adapted for loading of pigs on a first platform, when this first platform is in a horizontal position relative to a floor surface. The hand truck is then tilting 90°, so that the weight of the pig moves to the second platform. After 90° tilting, the second platform is horizontal and the first platform is vertically orientated. The bottom of the second platform is provided with four small wheels that allow movement of the hand truck over surfaces that are even and smooth. The first platform is provided with bigger wheels that can be pivoted to and from the first platform. This pivoting is necessary in order to allow loading of the pig on the first platform. The bigger wheels, when pivoted away from the first platform and locked into position, can be used for moving the hand truck by tilting the first platform backwards. The big wheels allow transport of the truck over longer distances and uneven surfaces. A disadvantage with the disclosed hand truck is that it is bulky and is not suitable for passing through narrow passages.

Summary of the invention

It is an object of the present invention to at least partly overcome the above problems, and to provide an improved hand truck suitable for passing through narrow passages. This object is achieved by a hand truck as defined in claim 1.

The hand truck comprises a frame, a load platform protruding from the frame, and having a rear portion attached to the frame, and a front portion facing away from the load platform, a first wheel for supporting the load platform, and rotatably connected to a first primary axis, a second wheel for supporting the load platform, spaced apart from the first wheel, and rotatably connected to a second primary axis, a first turning unit adapted to turn the first wheel in relation to the frame about a first secondary axis extending orthogonally to the first primary axis, and a second turning unit arranged to turn the second wheel in relation to the frame about a second secondary axis extending orthogonally to the second primary axis, and the first turning unit is adapted to turn the first wheel at least 90° in relation to the frame, and the second turning unit is adapted to turn the second wheel at least 90° in relation to the frame. The hand truck is characterized in that the first and second wheels are arranged to support the rear portion of the load platform, and the hand truck comprises at least one third wheel arranged to support the front portion of the load platform, and the third wheel is smaller than the first and second wheels and arranged pivotable in relation to the load platform.

The invention facilitates transportation of elongated goods through a narrow passage by moving the truck in a sideway direction. This is achieve by the combination of larger wheels supporting the rear portion of the platform and able to turn at least 90° in relation to the frame, and at least one smaller wheel rotatable or pivotable in relation to the load platform and supporting the front portion of the load platform.

The hand truck of the present invention can be moved in a forward direction in the same way as a traditional hand truck by tilting the frame and by that releasing the load platform from a ground level. When the hand truck is moved in the forward direction, the first and second wheels are positioned in a first position relative the frame. In the first position, the first and second wheels are disposed with their primary axes orthogonal to the direction in which the load platform is protruding from the frame. However, the hand truck of the present invention can also be moved without tilting the frame backwards. Due to the at least one third wheel supporting the load platform, the truck can remain in an upright position during loading and movement of the truck. By turning the first and second wheels to a second position with their primary axes orthogonal to the first position, it is possible to move the truck sideways in an upright position. Due to the fact that the third wheel is rotatable in relation to the load platform, the third wheel is automatically moved in parallel with the first and second wheels depending on the direction of the movement. Thus, the present invention makes it possible to move the truck sideways with the frame in an upright position. Therefore, less space is required for moving the hand truck from one place to another. This allows the hand truck to be used in narrow spaces, such as narrow corridors.

Further, the wheels are parallel to a length of the platform when the wheels are in the first position, as shown in figure 10a, and the wheels are orthogonal to the length of the platform, when the wheels are in the second position, as shown in figure lOd. Thus, the length of the hand truck is smaller in the second position than in the first position. When the wheels are turned to the second position, they do not protrude from the frame in the same way as in the first position. This fact further contributes to improve the ability of the hand truck according to the invention to move goods through narrow passages.

The first turning unit is adapted to turn the first wheel in relation to the frame between a first position and a second position so that the first wheel is turned at least 90° between the first and second position. The second turning unit is adapted to turn the second wheel in relation to the frame between a first position and a second position so that the second wheel is turned at least 90° between the first and second position. This enables movement of the truck in a forward direction as well as a sideway direction.

Because the hand truck, and thus the load platform, does not need to be tilted during use of the hand truck, the risk for dislodging of the load on the hand truck is decreased. This improves the safety for the user of the hand truck. The physical strength needed to move the hand truck is also decreased compared to known hand trucks that need to be tilted backwards prior to movement in order to release the load platform from the ground level, or compared to hand trucks that need to be pushed using four small wheels.

Because the load on the hand truck rests not solely on the first and second wheels of the hand truck, the wheels can be turned easily. All wheels can even be turned during movement of a loaded hand truck. Thus, the safety, efficiency and effectively of the hand truck have been improved.

According to an embodiment of the invention, the diameter of the first and second wheels is at least twice the diameter of the third wheel. In one embodiment, the diameter of the first and second wheels is at least three times as large as the diameter of the third wheel. The at least one third wheel is positioned in the proximity of a front portion of the load platform, such that the load platform remains in position, without tilting, during loading and movement. The third wheel is smaller than the first and second wheels. Suitably, the diameter of the third wheel is less than half the diameter of the first and second wheels. The first and second wheels should be large enough to carry the whole weight of the load, when the truck is moved in a tilted position. Since the third wheel carries the weight together with the first and second wheel when the truck is moved in an upright position, the third wheel can be made smaller than the first and second wheels. Since the third wheel is positioned under the load, the height of the third wheel determines the distance between the ground level and the load platform. It is advantageous to have a small third wheel in order to reduce the distance between ground and the load platform and thereby facilitating loading of the truck. In the prior art, the hand truck is pushed using four small wheels positioned under the platform. The truck of the invention uses two larger wheels and at least one small wheel for moving the hand truck. This allows movement of the hand truck over uneven floor surfaces, because the larger wheels do not get stuck in ridged or holes in the floor surface. The larger side wheels thus improve convenience and comfort for the user of the hand truck.

The load platform is designed for supporting a load carried by the truck. The frame and the load platform form a frame body. Suitably, the frame body has an L-shaped cross-section and the frame extends upwardly from the load platform. Suitably, the frame is elongated in a first direction along a longitudinal axis, and the load platform protrudes in a direction orthogonal or close to orthogonal to the longitudinal axis of the frame.

According to an embodiment of the invention, the load platform has an upper side and a bottom side and said third wheel is attached to the bottom side of the load platform, and the first and second wheels are operatively connected to the rear portion of the load platform and extends below the bottom side of the load platform in order to support the rear portion of the load platform.

According to an embodiment, the third wheel is a caster wheel. A caster or castor wheel may be defined as a single, double, or compound wheel that is designed to be mounted to the bottom of an object, such as the load platform, to enable that object to be easily moved. A caster wheel comprises a primary axis around which the wheel rotates. The wheel is mounted in a frame or fork, which comprises an additional joint above the fork comprising a secondary axis extending orthogonally to the primary axis of the wheel. This joint allows the fork to freely rotate or pivot about 360°, thus enabling the wheel to roll in any direction. This joint allows for the rotational or pivotable movement of the third wheel in relation to the platform.

In one embodiment, the hand truck comprises one third wheel for supporting the load platform. In another embodiment, the hand truck comprises two third wheels for supporting the load platform. If the truck has two third wheels for supporting the load platform, the truck becomes more stable and may enable the truck to carry a heavier load. The hand truck may comprise a wheel assembly comprising two wheel members spacedly supported at the frame. A first wheel member comprises the first wheel rotatably attached to the first primary axis and a second wheel member comprises the second wheel rotatably attached to the second primary axis. The wheel members may be disposed at different positions at the frame in relation to the load platform. Suitably, the primary axes are positioned behind the rear portion of the load platform, and accordingly on the side of the load platform.

According to an embodiment, the first wheel and the second wheel are adapted to turn independently around the respective primary axes and independently around the respective secondary axes. Thus, it is possible to place the wheels at different angles relative to each other to decrease the turning radius of the truck. Therefore, the hand truck can even be used in small corridors that have sharp corners, such as 90° corners. According to another embodiment, the first turning unit comprises a first turning rod extending upwardly along the first secondary axis, and a first rod handle positioned at an upper portion of the first turning rod, whereby the first turning rod is attached to the first primary axis such that the first wheel is turned upon turning of the first rod hand le, and whereby the second turning unit comprises a second turning rod extending upwardly along the second secondary axis, and a second rod handle positioned at an upper portion of the second turning rod, whereby the second turning rod is attached to the second primary axis such that the second wheel is turned upon turning of the second rod handle. The rod handle is in direct contact with the primary axis of the wheel members. This provides for a simple construction, whereby the wheels can be turned by turning the rod handle with little effort from the user. The turning units are easy to operate. Turning of the wheels can be performed by a person standing upright behind the frame. The turning of the wheels can also be performed during movement of the hand truck and independent on the weight of the load or the evenness of the floor surface. According to one embodiment, the first wheel defines a first plane and the first rod handle extends parallel to the first plane, and the second wheel defines a second plane and the second rod handle extends parallel to the second plane. The first and second rod handles are elongated in parallel with the first and second plane of the wheels respectively. This embodiment allows the handles to be folded against the frame. This decreases the space needed for storage of the hand truck.

According to another embodiment, the first turning unit comprises a first locking mechanism adapted to lock the position of the first wheel, and the second turning unit comprises a second locking mechanism adapted to lock the position of the second wheel. Locking of the wheels prevents the wheels from unintentional turning. This is advantageous when moving a loaded hand truck, especially when moving over an uneven floor surface, where the unevenness of the surface may cause the wheels to turn unintentionally. According to one embodiment, the first locking mechanism is adapted to lock the first wheel in two orthogonal positions, and the second locking mechanism is adapted to lock the second wheel in two orthogonal positions. Because the wheel members can be turned independently, the hand truck can be moved in multiple directions, even when the wheels are locked in a position.

According to an embodiment, the first turning rod is at least partly concealed by a first sleeve coaxially coupled to the first turning rod, and the second turning rod is at least partly concealed by a second sleeve coaxially coupled to the second turning rod. The sleeve can be used to protect the turning unit and the rod from wear and tear. The sleeve can be made of a metal or plastic material. Pa rt of the sleeve can be made of a softer material. Such softer material can be used to protect surroundings or the user during use of the hand truck. According to one embodiment, the first and the second locking mechanism comprise each a locking plate attached to an upper portion of the respective first and second sleeve and extending parallel to the rod handle, whereby the locking plate com prises at least two locking slots extending as holes through the locking plate, which holes optionally are connected by a slit, and a locking means attached to the rod handle and passed through the holes adapted to move the rod handle between the locking slots, and optionally a resilient element coaxially coupled on the respective first and second rod handle, whereby the resilient element is adapted to apply a downward force on the respective first and second rod handle to ensure engagement of the respective first and second rod handle in the locking slot on the respective first and second locking plate. The locking mechanism is simple and easy to manufacture at low cost. The turning unit with such a locking mechanism can be provided on existing hand trucks. The mechanism can be used without much effort from the user. The locking mechanism can even be used during movement of the hand truck.

According to an embodiment, the rear portion of the load platform is pivotally attached to the frame. This embodiment allows the load platform to be folded against the frame. This decreases the space needed for storage of the hand truck.

According to one embodiment, the frame comprises two telescopic handles adapted to be hold by a user of the hand truck. Telescopic arms can be folded and adapted in length. This embodiment improves the safety and convenience for the user that can adapt the length of the handle to his/her own length. This also decreases the space needed for storage of the hand truck.

The object is also achieved by a method for turning wheels of a hand truck, comprising applying an upward force, in a direction away from the load platform, on the respective first and second rod handle to disengage the rod handle from a locking slot, followed by turning the respective first and second rod handle to position the rod handle into another locking slot, and releasing the force to engage the respective first and second rod handle with the other slot.

The turning unit can be used by a simple push, turn and release of the rod handle. The force or strength needed to move the rod handle depends on the strengths of the resilient element. The function of the resilient element is to engage the rod handle in the locking slot. Not much physical strength is needed to turn a wheel member of the hand truck.

Brief description of the drawings

The invention will now be explained more closely by the description of different embodiments of the invention and with reference to the appended figures.

Fig. 1 shows a perspective view of a hand truck with wheels in a first position.

Fig. 2 shows a perspective view of a hand truck with wheels in a first and a second position.

Fig. 3 shows a perspective view of a hand truck with wheels in a second position.

Fig. 4 shows a rear view of the hand truck.

Fig. 5 shows a front view of the hand truck.

Fig. 6 shows a cross section view of a turning unit.

Figs. 7a-b show a bottom view of the hand truck having one or two caster wheels.

Fig. 8 shows a cross section view of a locking mechanism.

Fig. 9 shows a top view of a rod handle and a locking plate.

Figs. lOa-d illustrate the turning of a hand truck and moving the truck through a narrow passage.

Detailed description of various embodiments of the invention

Figures 1 to 5 show an embodiment of the hand truck according to the present invention. The hand truck comprises a load platform 1 and a frame 2. The frame is elongated and extends upwardly from the load platform resulting in an L-shaped cross section of the hand truck. As shown in the figures, the frame 2 may comprise two parallel rods extending upwardly along a longitudinal axis L from the load platform and crossbars 3, 3b extending parallel to the load platform. One or more cross bars improve the stability of the hand truck.

The frame 2 may further comprise handles 2a, 2b that can be used by a user to move the hand truck. Preferably, the handles may comprise telescopic arms 45, which allow the length of the handles on the frame to be varied and adapted to a length of a user. Further, telescopic arms 45 allow the length of the handles to be minimized such that the hand truck occupies less storage space when not being used.

The load platform 1 protrudes crosswise or substantially perpendicular in relation to the frame. The load platform may be pivotally attached to the frame (as indicated by the dotted line in figure 3). This pivotally attachment allows the load platform to be folded towards the frame such that less storage space is required when the hand truck is not being used. The load platform has a length I as shown in figure 7b. The size of the load platform may vary. Two wheel members 4a, 4b are attached to the frame 2. As shown in figure 1 to 5, the wheel members are positioned at a rear portion of the load platform and spaced apart by the load platform, such that a first wheel member 4a is placed on one side of the platform and a second wheel member 4b is placed on another side of the platform. Any attachment means may be used to attach the wheels to the platform. Additional crossbars 5a-b for mounting the wheel members to the frame may be used to attach the wheel members to the frame. The additional crossbars 5a-b for mounting the wheel members may extend rearwards from the frame in relation to the load platform. The load platform 1 is present on a front side of the frame.

The first and second wheel member 4a, 4b comprise each a wheel 6a, 6b and a primary axis xla, xlb around which the wheel rotates. The first wheel defines a first plane extending orthogonally to the first primary axis and the second wheel defines a second plane extending orthogonally to the second primary axis. The wheels 6a, 6b may be any type of wheels. The wheels may have hard or soft tires attached to a wheel rim, for example rubber tires for convenience of using the hand truck.

The hand truck also comprises at least one additional third wheel 7 positioned under the load platform. The additional wheel 7 is arranged pivotable in relation to the load platform 1. The wheel 7 is preferably pivotable 360° in relation to the load platform. The wheel 7 may be a caster wheel.

The load platform 1 has a rear portion 21 attached to the frame 2 and a front portion 20 facing away from the load truck. The load platform also has a an upper side 23 adapted for supporting goods transported by the hand truck, and a bottom side 22 facing the ground or floor when the hand truck is used. The third wheel 7 is arranged to support the front portion 20 of the load platform. The third wheel 7 is connected to the front portion 20 of the load platform. The third wheel 7 is attached to the bottom side 22 of the load platform 1. The first and second wheels 6a-b are operatively connected to the rear portion of the load platform and arranged to support the rear portion 21 of the load platform. In this example, the first and second wheels are connected to the frame, and the load platform is connected to the frame. The first and second wheels 6a-b extend below the bottom side 22 of the load platform, and by that support the rear portion 21 of the platform. In figure 7a, one caster wheel 7 is shown positioned at the front portion 20 of the load platform 1. The rear portion 21 of the load platform is attached to the frame 2. The wheel 7 is attached to a bottom side 22 of the load platform 1.

In figure 7b two caster wheels 7a-b are shown positioned at the front portion 20 of the load platform. A clearance C (figure 2) is present between the load platform and a ground level or floor surface g on which the wheel members rest. Castor wheels are available in various sizes, and are commonly made of rubber, plastic, nylon, aluminum, or stainless steel. Additionally, a caster typically includes a small amount of offset distance between the secondary axis of the fork and the primary axis of the wheel. When the caster is moved and the wheel is not facing the correct direction, the offset will cause the wheel assembly to rotate around the secondary axis of the frame to follow behind the direction of movement. If there is no offset, the wheel will not rotate if not facing the correct direction, either preventing motion or dragging across the ground. When in motion along a straight line, a caster wheel will tend to automatically align or pivot to, and rotate parallel to the direction of transport or movement. A consequence of this is that the hand truck naturally tends to move in a straight direction. Precise steering is not required because the caster wheels tend to maintain a straight motion. This is also true during turns of the hand truck. The caster wheel rotates perpendicular to a turning radius and provides a smooth turn. Hereby, the front wheel can rotate at different velocities and with different turning radius compared to the rear wheels member depending on how tight a turn is made. An angle and distance between the primary and secondary axes and the joint can be adjusted for different types of performance. The first and second wheel member 4a, 4b may also be caster wheels. Caster wheels are also available with a locking mechanism on the wheel member to prevent the wheel from turning around the secondary axis of the caster wheel member. Such a locking mechanism may be convenient when moving the hand truck.

The hand truck comprises a first and a second turning unit adapted to turn the first wheel 6a and the second wheel 6b respectively. Figure 6 shows a cross section of a turning unit. The turning unit is adapted to turn the wheel 6a, 6b in relation to the frame 2 around a secondary axis x2a, x2b, which axes extends orthogonally to the primary axis xla, xlb. The turning unit comprises a turning rod 8a, 8b, which extends upwardly along the secondary axis x2a, x2b and substantially parallel to the respective plane of the wheel 6a, 6b.

The turning rod 8a, 8b may be partially or completely concealed by a sleeve 9a, 9b, whereby the sleeve is coaxially coupled to the respective turning rod 8a, 8b. Connection means 37, 38 may be used to connect the sleeve to the turning rod as shown in figure 8.

A rod handle 10a, 10b is positioned at an upper portion of the respective turning rod 8a, 8b. The rod handle may be fixedly or pivotally attached to the turning rod. The first wheel member 4a is turned upon turning of the first rod handle 10a and the second wheel member 4b is turned upon turning of the second rod handle 10b. The wheels members 4a, 4b can be turned independently.

The wheel members may be locked into a position such that the wheels are prohibited to turn. The wheel members 4a, 4b may be locked in the first position (figure 1). The wheel members 4a, 4b may be locked in a second position, whereby the wheels are aligned with each other, (figure 3, lOd). Alternatively, the one wheel member may be locked in the first position and the other wheel member may be locked in the second position. This enables a rotational movement of the hand truck (figure 2, lOb-lOc). Figure lOa-b illustrate turning of a hand truck and moving the truck through a narrow passage. In figure 10a, the first and second wheels are locked in a first position, whereby the wheels are parallel to each other, which enables movement of the hand truck backwards and forwards. In figures lOb-c, the first wheel is locked in the first position and the second wheel is locked in the second position, which enables a rotational movement of the hand truck. In figure lOd, the first and second wheels are both locked in a second position, whereby the wheels are aligned with each other, which enables movement of the hand truck in a sideway direction. The hand truck can now pass through a narrow passage while carrying an elongated load, as shown in figure lOd.

In another embodiment, the wheel members can be locked in a third position (not shown), whereby the wheels are positioned between the first and second position. The wheels may be positioned at an angle of about 45° in relation to the rear portion 21 of the load platform 1. In this position, the first primary axis of the first wheel is crosswise or perpendicular positioned in relation to the second primary axis of the second wheel.

Figure 8 shows an example of a locking mechanism. The locking mechanism comprises each a locking plate 30 attached to an upper portion of the respective first and second sleeve. This locking plate extends parallel to the rod handle 10a, 10b. The locking plate comprises at least two locking slots 11-1, 11-2. These slots extend as holes through the locking plate, which holes are connected by a slit 31 as shown in figure 9. A locking means 34, such as a locking pin 34 and a stopper 35 are attached to the rod handle and passed through the hole of the lock 11. The locking means 34 is adapted to move the rod handle 10 from a first locking slot 11-1 to a second locking slot 11-2, and back.

The locking mechanism may optionally comprise a resilient element 36 coaxially coupled on the respective first and second locking means and respective first and second rod handle. The resilient element is adapted to apply a downward force on the respective first and second rod handle to ensure engagement of the respective first and second rod handle in the locking slot on the respective first and second locking plate.

The respective first and second locking mechanism may comprise each two locking slots 11-1, 11-2. When the first rod handle 10a is positioned in the first locking slot 11-1 and the second rod handle 10b is positioned in a corresponding first locking slot, the respective first wheel 6a and the second wheel 6b are in the first position, parallel and enabling movement of the hand truck backwards and forwards (figure 1, 10a).

When the first rod handle 10a is positioned in the second locking slot 11-2 and the second rod handle 10b is positioned in a corresponding second locking slot, the respective first wheel 6a and the second wheel 6b are in the second position, aligned and enabling movement of the hand truck from left to right (figure 3, lOd). As shown in figure 2, 10b, 10c, one rod handle may be locked in the first locking slot 11-lb and the other rod handle may be locked in the second locking slot ll-2a. The first primary axis xla of the first wheel member 4a is crosswise or perpendicular positioned in relation to the second primary axis xlb of the second wheel member 4b.

The locking mechanism may comprise a third locking slot (not shown) positioned between the first and second locking slot. The third locking slot can be used to position the respective first and second wheel member in a third position. This further enables a rotational movement of the hand truck.

Alternatively, the locking mechanism comprises at least two locking slots 11-1, 11-2 extending as openings between two edges of an upper portion of the respective sleeve 9a, 9b (not shown). In this embodiment, the rod handle 10a, 10b are pivotally attached to the respective turning rod 8a, 8b. A resilient element is coaxially coupled on the respective turning rod and attached to the respective rod handle. The resilient element, such as a spring, is adapted to apply a downward force on the respective rod handle to ensure engagement of the respective rod handle in the locking slot on the respective sleeve. In this alternative embodiment, the wheel members can be turned into different positions by applying an upward force on the respective first and second rod handle to disengage the rod handle from a locking slot. Subsequently, the respective first and second rod handle can be turned to position the rod handle into another locking slot. By releasing the force the respective first and second rod handle will engage with the other slot due to the pulling strength of the resilient element.

In yet another locking mechanism (not shown) the at least two locking slots 11-1, 11-2 are positioned at a bottom portion of the sleeve 9a, 9b. The slots extend as openings between two slanted edges of a bottom portion of the respective first and second sleeve. The outline of the openings corresponds to the outline of the respective first and second primary axis xla, xlb. The slots are adapted to lock the respective first and second sleeve on said respective first and second primary axis. In this embodiment, the rod handle 10a, 10b may be pivotally attached to the respective turning rod 8a, 9b. A resilient element may be coaxially coupled to an upper portion of the sleeve and attached to the rod handle. The resilient element is adapted to apply a downward force on the sleeve to ensure engagement of the locking slot 11 on the primary axis. The sleeve can be disengaged from the slot by pulling the rod handle and thus the sleeve upwards.

The wheel can be turned into different positions by applying an upward force on the rod handle to disengage the sleeve from a locking slot. Subsequently, the handle can be turned to position the sleeve into another locking slot. By releasing the force the rod handle will engage with the other slot due to the pulling strength of the resilient element. Also in this embodiment, at least two locking slots enable the wheels to be locked independently in at least two positions.

The present invention is not limited to the embodiments disclosed but may be varied and modified within the scope of the following claims. For example different turning units and different locking mechanisms may be used.

Claims

1. A hand truck comprising:

- a frame (2),

- a load platform (1) protruding from the frame, and having a rear portion (21) attached to the frame (2) and a front portion (20) facing away from the load platform,

- a first wheel (6a) for supporting the load platform, and rotatably connected to a first primary axis (xla),

- a second wheel (6b) for supporting the load platform, spaced apart from the first wheel, and rotatably connected to a second primary axis (xlb),

- a first turning unit adapted to turn the first wheel in relation to the frame about a first secondary axis (x2a) extending orthogonally to the first primary axis, and

- a second turning unit arranged to turn the second wheel in relation to the frame about a second secondary axis (x2b) extending orthogonally to the second primary axis, and the first turning unit is adapted to turn the first wheel at least 90° in relation to the frame, and the second turning unit is adapted to turn the second wheel at least 90° in relation to the frame, characterized in that the first and second wheels are arranged to support the rear portion of the load platform, and the hand truck comprises at least one third wheel (7; 7a-b) arranged to support the front portion of the load platform, and the third wheel is smaller than the first and second wheels and arranged pivotable in relation to the load platform.

2. The hand truck according to claim 1, whereby the load platform has an upper side (23) and a bottom side (22) and said third wheel (7; 7a-b) is attached to the bottom side of the load platform, and the first and second wheels (6a-b) are operatively connected to the rear portion of the load platform and extend below the bottom side (22) of the load platform.

3. The hand truck according to claim 1 or 2, whereby the diameter of the first and second wheels (6a, 6b) is at least twice the diameter of the third wheel (7; 7a-b).

4. The hand truck according to any of the previous claims, whereby the third wheel (7) is a caster wheel.

5. The hand truck according to any of the previous claims, whereby the first wheel and the second wheel are adapted to turn independently around the respective primary axes and independently around the respective secondary axes.

6. The hand truck according to any of the previous claims, whereby the first turning unit comprises a first turning rod (8a) extending upwardly along the first secondary axis (x2a), and a first rod handle (10a) positioned at an upper portion of the first turning rod, whereby the first turning rod (8a) is attached to the first primary axis such that the first wheel is turned upon turning of the first rod handle, and whereby the second turning unit comprises a second turning rod (8b) extending upwardly along the second secondary axis (x2b), and a second rod handle (10b) positioned at an upper portion of the second turning rod, whereby the second turning rod (8b) is attached to the second primary axis such that the second wheel is turned upon turning of the second rod handle.

7. The hand truck according to claim 6, whereby the first wheel (6a) defines a first plane and the first rod handle (10a) extends parallel to the first plane, and the second wheel (6b) defines a second plane and the second rod handle (10a) extends parallel to the second plane.

8. The hand truck according to any of the previous claims, whereby the first turning unit comprises a first locking mechanism adapted to lock the position of the first wheel (6a), and the second turning unit comprises a second locking mechanism adapted to lock the position of the second wheel (6b).

9. The hand truck according to claim 8, whereby the first locking mechanism is adapted to lock the first wheel (6a) in two orthogonal positions, and the second locking mechanism is adapted to lock the second wheel (6b) in two orthogonal positions.

10. The hand truck according to claim 8 or 9, whereby the first turning rod is at least partly concealed by a first sleeve (9a) coaxially coupled to the first turning rod, and the second turning rod is at least partly concealed by a second sleeve (9b) coaxially coupled to the second turning rod.

11. The hand truck according to claim 10, whereby the first and the second locking mechanism comprises each a locking plate (30a) attached to an upper portion of the respective first and second sleeve (9a ) and extending parallel to the rod handle (10a), whereby the locking plate comprises at least two locking slots (11-1, 11-2) extending as holes through the locking plate, which holes are connected by a slit (31) and a locking means (34) attached to the rod handle and passed through the holes adapted to move the rod handle between the locking slots, and optionally a resilient element (36) coaxially coupled on the respective first and second rod handle, whereby the resilient element is adapted to apply a downward force on the respective first and second rod handle to ensure engagement of the respective first and second rod handle in the locking slot on the respective first and second locking plate.

12. The hand truck according to any of the previous claims, whereby the rear portion of the load platform is pivotally attached to the frame.

13. The hand truck according to any of the previous claims, whereby the frame comprises two telescopic handles (45) adapted to be hold by a user of the hand truck.