GB2180801A

GB2180801A - Convertible hand truck

Info

Publication number: GB2180801A
Application number: GB08523753A
Authority: GB
Inventors: Alan Walter Cox
Original assignee: Black and Decker Inc
Current assignee: Black and Decker Inc
Priority date: 1985-09-26
Filing date: 1985-09-26
Publication date: 1987-04-08
Anticipated expiration: 2005-09-26
Also published as: GB8523753D0; GB2180801B

Abstract

A hand truck has a main frame (1) at one end of which a pair of wheels (2) is mounted for rotation about a common axle (3). Two further castor wheels (12) are mounted on the main frame (1) at the other end thereof. The truck has a handle (5) of closed loop form pivotally adjacent the other end thereof. The handle (5) is movable with respect to the main frame between positions allowing the truck to be used as a porter's truck supported by the pair of wheels (2) or as a trolley supported by both the pair of wheels (2) and the castor wheels (12).

Description

SPECIFICATION Hand truck This invention relates to a wheeled hand truck and in particular to a hand truck that can be used in a first mode with a single set of wheels engaging the ground and in a second mode with at least one further wheel engaging the ground.

In a known form of such a truck, a main frame of the truck is provided with a pair of wheels mounted on a common axle at one end and at the other end of the frame a further two wheels are provided and a handle is pivotally connected to the frame. In the first, two-wheeled mode of use, the handle is clamped in a position where it forms an extension of the main frame and the truck is used simply as a traditional two wheeled hand truck with only the pair of wheels on the ground and with the main frame inclined at an angle of perhaps about 45 degrees to the ground. In this orientation, the weight of a load is usually supported partly by the wheels and partly by the user.In the second mode of use, all four wheels rest on the ground, the main frame of the truck is approximately parallel to the ground and the handle is pivoted relative to the frame through an angle perhaps in the range of 45 to 90 degrees so that it extends upwardly from the main frame. The second, four-wheeled, mode of use is particularly suitable for carrying heavy loads as the wheels support the whole weight of any load the user having merely to manoeuvre the truck.

In the known form of truck the handle must be of a reasonable length so that in the fourwheeled mode of use when the pivoted end of the handle is close to the ground, the free end is at a height reasonably convenient for the user. When the truck is used in the twowheeled mode, however, with the handle forming an extension of the main frame, it is important that the combined length of the main frame and handle should not be too long or the truck becomes awkward to manoeuvre.

It is therefore necessary to limit the length of the main frame and this in turn limits the length of the load carrying platform when the truck is used in the four-wheeled mode.

It is an object of the invention to provide an improved form of wheeled hand truck which at least mitigates the disadvantages described above.

According to the present invention a hand truck has a main frame, a set of wheels mounted for rotation about a common axis in the region of one end of the main frame; at least one further wheel spaced from said one end of the main frame and a handle part pivotally coupled between its ends to the other end of the main frame, wherein the pivotal coupling of the handle part is closer to one end thereof than to the other whereby longer and shorter ends of the handle part are defined, and the handle part is pivotable between a first position, for use when the truck is being supported by said set of wheels only, in which the longer end lies adjacent the main frame and the shorter end provides a handle extending from the main frame, and a second position, for use when the truck is also to be supported by the further wheel or wheels, in which and the longer end defines a handle extending from the main frame.

Because different ends of the handle part provide the handle in the two modes of use and these ends are of different length the disadvantage referred to above can be avoided.

In the first mode of use the handle is relatively short and the main frame can therefore be comparatively longer while in the second mode of use the longer handle allows the free end of the handle to be at a convenient height while the comparatively longer main frame provides a load carrying platform of increased length.

Preferably, in the first position the longer end of the handle part lies on top of the main frame and in the second position the shorter end of the handle part abuts the underneath of the main frame. The abutment of the shorter end against the main frame limits the pivotal movement of the handle.

Locking means are preferably provided for locking the handle part in the first position.

The locking means are preferably provided on the main frame in the region of said one end thereof. The restraining force required to hold the handle part in its first position is relatively small at that end of the main frame as a result of its distance from the pivotal connection.

The locking means may comprise at least one latch member rotatable between a locking position in which a part of the latch member prevents movement of the longer end of the handle part away from the main frame and a released position in which the latch member does not obstruct such movement.

The longer and shorter ends of the handle are preferably inclined at an angle to one another. The angle of inclination may be about 45 degrees. The handle part is preferably pivotable through an angle in the range of 100 degrees to 150 degrees relative to the frame.

More particularly the handle part may be pivotable through an angle of the order of 3/8ths of a revolution. Thus, if the longer end of the handle part is approximately parallel to the main frame in its first position it will be pivotable to a position, which is its second position, in which it is inclined at an angle of the order of 45 degrees away from the main frame, this being a convenient angle for the second mode of use. At the same time if te shorter end of the handle part is approximately parallel to the main frame in its second position then it will be inclined to the main frame in its first position and this is convenient for the first mode of use.

Said at least one -further wheel preferably comprises two wheels mounted on opposite sides of the main frame; an alternative arrangement would be to provide a single further wheel in the middle of the main frame, but that would provide a less stable arrangement.

The or each further wheel is preferably swivelably mounted. This facilitates manoeuvring of the truck in its second mode of use.

The or teach further wheel is preferably mounted at said other end of the main frame.

This again improves the stability of the truck.

The longer end of the handle part is preferably at least twice as long as the shorter end.

In one embodiment of the invention to be described the longer end is of the order of three times the length of the shorter end. Such a ratio of lengths enables a load carrying platform of reasonable length to be provided without the truck being unduly long for use in its first mode.

The longer and/or shorter ends of the handle may be of generally "U" shaped configuration.

The invention also provides a hand truck having a main frame, a set of wheels mounted for rotation about a common axis in the region of one end of the main frame, at least one further wheel spaced from said one end of the main frame and a handle part pivotally coupled to the other end of the main frame, wherein the handle part is in the form of an endless loop.

By way of example a hand truck embodying the invention will now be described with reference to the accompanying drawings, of which: Fig. 1 is an exploded view of the truck, Fig. 2 is a perspective view of the truck arranged for use as a two-wheeled truck and standing on end, and Fig. 3 is a perspective view of the truck arranged for use as a four-wheeled truck.

The hand truck shown in the drawings generally comprises a main frame 1, a pair of wheels 2 mounted on a common axle 3 beneath a front end of the frame, two further wheels 4 mounted beneath opposite sides of the rear end of the frame and a handle part 5 pivotally connected to the rear end of the frame. It will be understood that in describing the structure of the hand truck, it is assumed that the truck is oriented with its main frame 1 as in Fig. 3 and words such as "beneath" should be construed accordingly.

The main frame 1 comprises a tubular part 6 of "U" shaped configuration bolted to turned up edge portions 23 of a plate 7 of generally "L" shaped cross-section which provides the foot-plate of the truck. Triangular portions 8 are cut out of the plate 7 and bent perpendicular thereto; the distal ends of these portions provide mountings for the axle 3. A cross-member 9 is fastened between the limbs of the "U" shaped part 6 about midway along the length of those limbs and another cross-member 10 is fastened between the limbs close to their roots. Wheel assemblies 12 which include the wheels 4 are fastened to the cross-member by threaded spigots which pass through apertures 11 in pressed out parts 13 of the cross-member 10 and are secured to the cross-member by nuts housed in the recesses formed by the pressed out parts.

Each wheel 4 is swivellable about the central axis of its aperture 11.

The wheels 2 are held on the axle 3 by spring clips 14, and washers 15 are provided between the triangular portions 8, wheels 2 and spring clips 14.

A respective latching assembly comprising a pivot block 16, latch member 17 and nut 18 is fixed to an upper region of each triangular portion 8 by a nut 19 and bolt 20. The pivot block 16 has a through bore 21 and the nut 18 is located in the block 16 with its screw threaded hole in alignment with this bore. The lower portion of the member 17 is screw threaded and is inserted into the bore 21 from above and screwed into the nut 18. The upper end of the member 17 is bent through at least a right angle to provide a projecting part 22.

The handle part 5 comprises a length of tube formed into an endless loop and is divided by its pivotal connection to the main frame into a longer end 25 and shorter end 26 both of "U" shape. The longer end of the handle part is bent through an angle of about 45 degrees at a position spaced only a short distance from the pivotal connection to the main frame and the longer end is of the order of three times the length of the shorter end.

The handle part 5 is connected outside the main frame 1.

The hand truck has two principal intended modes of use. For the first mode of use (the two wheel mode) the handle is pivoted to the position shown in Fig. 2 with the longer end 25 resting on top of the plate 7 and the shorter end 26 extending from the main frame at an angle thereto and providing a handle conveniently positioned for a user. In order to move the handle to this position the pivot blocks 16 have to be rotated such that their projecting parts 22 are moved towards the rear of the frame 1. Once the handle is in position the pivot blocks 16 are rotated so that their projecting parts 22 move back towards the front of the frame 1 and engage in holes 27 formed in the longer end 25 of the handle part. The truck can then be used as any conventional two wheeled hand truck and the wheels 4 are normally well clear of the ground but also provide a rear support for the truck if the user wishes to rest the truck with the main frame approximately parallel to the ground. The truck can also be rested on the footplate with the main frame approximately perpendicular to the ground as shown in Fig.

2.

To convert the truck for the second mode of use the latch pivot blocks 16 are rotated such that the projecting parts 22 of the latch members 17 are disengaged from the holes 27 and the handle part is pivoted through an angle of the order of three eighths of a revolution to the position shown in Fig. 3 with the shorter end 26 of the handle part abutting the underneath of the frame 1 and the longer end 25 extending upwardly from the main frame at an angle of about 45 degrees to the ground and with all four wheels resting on the ground. In this second mode of use downward movement of the longer end of the handle beyond the position shown in Fig. 3 is prevented by the abutment of the shorter end 26 with the main frame 1; however, the handle is not locked in position and it is possible for the user to move it to a more upright position which may be of value when manoeuvering the truck in confined spaces and at other times.

While in the embodiment described the longer end 25 of the handle part is "U" shaped, it would be possible for other shapes to be employed while maintaining the same pivotal connection of the handle to the main frame.

Furthermore, the handle part could be pivotally connected to the frame at a single central position rather than at both sides and in this case a wide variety of different shapes for both the longer and shorter ends could be employed. For example either end could be "T" shaped.

Claims

1. A hand truck having a main frame, a set of wheels mounted for rotation about a common axis in the region of one end of the main frame, at least one further wheel spaced from said one end of the main frame and a handle part pivotally coupled between its ends to the other end of the main frame, wherein the pivotal coupling of the handle part is closer to one end than the other whereby longer and shorter ends of the handle part are defined, and the handle part is pivotable between a first position, for use when the truck is being supported by said set of wheels only, in which the longer end lies adjacent the main frame and the shorter end provides a handle extending from the main frame and a second position, for use when the truck is also to be supported by the further wheel or wheels, in which the longer end defines a handle extending form the main frame.

2. A truck as claimed in claim 1 in which in the first position the longer end of the handle part lies on top of the main frame and in the second position the shorter end of the handle part abuts the underneath of the main frame.

3. A truck as claimed in claim 1 or 2 in which locking means are provided for locking the handle part in the first position.

4. A truck as claimed in claim 3 in which the locking means are provided on the main frame in the region of said one end thereof.

5. A truck as claimed in claim 3 or 4 in which the locking means comprise at least one latch member rotatable betwen a locking position in which a part of the latch member prevents movement of the longer end of the handle away from the main frame and a released position in which the latch member does not obstruct such movement.

6. A truck as claimed in any preceding claim in which the longer and shorter ends of the handle are inclined at an angle to one another.

7. A truck as claimed in claim 6 in which the angle of inclination is about 45 degrees.

8. A truck as claimed in any preceding claim in which the handle part is pivotable through an angle in the range of 100 degrees to 150 degrees relative to the frame.

9. A truck as claimed in claim 8 in which the handle part is pivotable through an angle of the order of three-eighths of a revolution.

10. A truck as claimed in any preceding claim in which said at least one further w.heel comprises two wheels mounted on opposite sides of the main frame.

11. A truck as claimed in any preceding claim in which the or each further wheel is swivelably mounted.

12. A truck as claimed in any preceding claim in which the or each further wheel is mounted at said other end of the main frame.

13. A truck as claimed in any preceding claim in which the longer end of the handle part is at least twice as long as the shorter end.

14. A truck as claimed in any preceding claim in which the longer and/or shorter ends of the handle are each of generally "U" shaped configuration.

15. A hand truck having a main frame, a set of wheels mounted for rotation about a common axis in the region of one end of the main frame, at least one further wheel spaced from said one end of the main frame and a handle part pivotally coupled to the other end of the main frame, wherein the handle part is in the form of an endless loop.

16. A hand truck having a main frame, a set of ground-engaging wheels mounted for rotation about a common axis in the region of one end of the main frame, at least one further wheel spaced from said one end of the main frame, and a handle part attached to the main frame, in which the handle part is movable between a first position used when the truck is supported by the set of wheels only and a second position used when the truck is supported by all the wheels and in which the movement of the handle part in the direction of its first position is limited by the engage ment of one portion of the handle with the main frame whilst movement of the handle part in the direction of its second position is limited by the engagement of another portion of the handle with the main frame.

17. A hand truck as claimed in claim 16 in which the handle part is pivotally attached to the main frame.

18. A hand truck as claimed in claim 16 or 17 in which the handle part is in the form of an endless loop.

19. A hand truck as claimed in any one of claims 16-18 in which the handle part is attached between its ends to the main frame in a manner such that longer and shorter ends of the handle are defined, movement to the first position being limited by engagement of the longer part with -the main frame, and movement to the second position is limited by the engagement of the shorter end with the main frame.

20. A hand truck as claimed in claim 19 in which the longer and shorter ends are inclined to one another.

21. A hand truck substantially as herein described with reference to and as illustrated by the accompanying drawings.