GB2449237A

GB2449237A - Hand tool for lifting and carrying building blocks

Info

Publication number: GB2449237A
Application number: GB0709173A
Authority: GB
Inventors: Michael Mcgowan
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-05-12
Filing date: 2007-05-12
Publication date: 2008-11-19
Also published as: GB0709173D0

Abstract

A hand tool for lifting and carrying building blocks comprises a generally elongate handle 1 coupled to first and second pivoting members 2,3 at each of its ends, respectively. Pivoting means 4 couples the first and second pivoting members such that each can rotate in a substantially vertical plane about a substantially horizontal axis, which may be a common axis A, when the hand tool is lifted by the handle. Each of the first and second members comprises a respective gripping means 50 for engaging a surface of a block to be lifted. In use, when the hand tool in lifted by the handle the first and second pivoting members are urged to rotate such that the gripping means are urged together, whereby a block positioned between them may be gripped and lifted. A spacer member 42 arranged between the first and second arms to separate them in a direction parallel to the pivot axis.

Description

1 2449237

HAND TOOL

Ficid of the Invention The present invention relates to a hand tool for lifting and carrying building blocks, and in particular, although not exclusively, to hand tools for lifting and carrying breeze blocks and bricks.

Background to the Invention

Hand tools for lifting and carrying a plurality of bricks are known, and are also referred to as brick tongs. A known brick tong comprises a rigid arm with a rigid jaw member extending generally perpendicularly from it at one end. A long handle member is pivotally coupled to the other end of the rigid arm, and extends from the pivot point towards the other end of the rigid arm. Attached to the arm handle is another jaw member, arranged so that as the tong is lifted by the handle, the handle is urged to pivot, so urging the jaw member attached to it to move towards the fixed jaw member at the other end of the rigid arm. Thus, if the tong is placed over a block or row of bricks with the jaw members positioned next to end surfaces of the block or row of bncks, as the handle is lifted the jaws engage the block or bricks, gripping the blocks or bricks firmly so that they can then be lifted with the tongs.

Although such brick tongs are useful in various applications, a disadvantage is that the block or bricks carried by them are not necessarily held level, and hence the tongs are not suited to use in actual laying of the block or bricks. On a related note, the angle at which the lifted block or bricks orientate themselves depends on the precise position on the handle at which the user grips and lifts the device. As a block or bricks are lifted with these brick tongs, the centre of gravity of the tongs and lifted material is not necessarily directly under the point of which the handle is grasped, and so as the device and objects are lifted there will in general be some rotation of the assembly relative to the user's hand. Clearly, the weights being lifted with such devices may be considerable, and any such motion is undesirable from a health and safety perspective.

I

Continuing on this theme, various health arid safety authorities have expressed concern in relation to the number of long term injuries experienced by construction site workers due to the carrying of asymmetric, miss-aligned and unsafe loads. The current general practice when carrying blocks is to carry them against the chest, held by two hands, raising the centre of gravity of the person canying the load to a level that can impair stability and endanger them when working at heights above ground level. In addition the practice of carrying blocks held against the chest to a working level above the ground exposes the person carrying the load to the danger of falling, where one hand may need to cease holding the load and take hold of a hand rail or other stable object close by. When a person carries a load on or about their chest, their ability to see where they are placing their feet can be impaired and lead to the danger of stumbling or falling with the risk of injury and damage to both the object carried and other persons nearby. It will be appreciated that carrying miss-aligned asymmetric loads, and in particular heavy blocks, on the person's body can result in spinal and RSI injuries.

It is an object of embodiments of the invention to provide hand tools suitable for lifting building components, such as building blocks and bricks, which obviate or mitigate at least one of the problems associated with the prior art.

Summary of the Invention

According to the present invention there is provided a hand tool for lifting and carrying building blocks, comprising: a generally elongate handle member having a first end and a second end; a first pivoting member; a second pivoting member; first coupling means arranged to couple a first end portion of the handle member to the first pivoting member; second coupling means arranged to couple a second end portion of the handle member to the second pivoting member; pivot means arranged to couple the first pivoting member to the second pivoting member such that each member can rotate in a substantially vertical place about a substantially horizontal pivot axis when the hand tool is lifted by the handle member, and wherein each of the first and second pivoting members comprises a respective gripping means for engaging and gripping a surface of a block to be lifted by the hand tool, the arrangement being such that when the hand tool is lifted by the handle member, the first and second pivoting members are urged to rotate such that the gripping means are urged together, whereby a block positioned between the gripping means may be gripped and lifted.

In certain embodiments the handle member is generally arcuate.

In certain embodiments the handle member comprises a rigid bar or arm.

Although the pivoting members may be arranged to pivot about different respective pivot axes, in certain embodiments the pivot means is arranged such that the first pivoting member and second pivoting member rotate about a common pivot axis.

Conveniently, the pivot means may comprise shaft means (e.g. a shaft, rod, bar, bush, shaft portion of a bolt etc.) received in a hole in the first pivoting member and a corresponding hole in the second pivoting member.

In certain embodiments the first pivoting member comprises a first arm having a first end and a second end, and the second pivoting member comprises a second arm having a respective first end and second end. The first and second arms may be arranged in crossed relationship to each other. For example, in certain embodiments the pivot means is arranged such that a point at which the arms cross is fixed and corresponds to a common pivot axis about which the first arm and the second arm can rotate.

In certain embodiments the first coupling means couples the first end portion of the handle member to a first end portion of the first arm and the second coupling means couples the second end portion of the handle member to a first end portion of the second arm.

The respective gripping means of each arm may be provided at the second end of each arm, and may be arranged to extend generally downwards from the second end of the respective arm when the hand tool is lifted by the handle means.

In certain embodiments the respective gripping means of each arm is arranged to provide a gripping surface which extends in a direction generally parallel to the rotational axis of each pivoting member.

The tool may further comprise a spacer member arranged between the first and second arms to separate them in a direction parallel to the pivot axis. In such cases, the handle member may have a substantially uniform thickness in a direction parallel to the pivot axis, the handle thickness being substantially equal to a thickness of the spacer member in a direction parallel to the pivot axis. In certain alternative embodiments, there is no spacer between the pivot members (e.g. arms).

In certain embodiments the arrangement of handle member, pivoting members, pivot means and coupling means is such that when the hand tool is lifted by the handle means, the first pivoting member is arranged to rotate in a vertical plane on one side of the handle means and the second pivoting member is arranged to rotate in a vertical plane on the other side of the handle means.

In certain alternative embodiments the handle member does not have uniform thickness, and comprises a thickened central portion to facilitate gripping and/or the reduce pressure.

In certain embodiments the handle member is a single, unitary component, whereas in alternative embodiments the handle member comprises an assembly of components.

In certain embodiments the first coupling means comprises shaft means attached to and extending from one of the handle means and first pivoting member, the shaft means being received in a slot provided in the other one of the handle means and first pivoting member. The slot may be arranged to permit limited rotation of the first pivoting member as the hand tool is lifted by the handle means.

Similarly, the second coupling means may comprise shaft means attached to and extending from one of the handle means and the second pivoting member, the shaft means being received in a slot provided in the other one of the handle means and second pivoting member. Again, in certain embodiments the slot of the second coupling means is arranged to permit limited rotation of the second pivoting member as the hand tool is lifted by the handle means.

In certain embodiments the hand tool further comprises a second handle member provided on at least one of the first and second pivoting members, the second handle member being positioned such that it can be gripped together with the first handle member by a single hand, the arrangement being such that when the second handle member is gripped together with the first handle member this prevents movement of the arm on which the second handle member is provided relative to the first handle member as the hand tool is lifted.

Certain embodiments also comprise a third handle member provided on the other one of the first and second pivoting members, the third handle member being positioned such that it can be gripped together with the first handle member and the second handle member by a single hand, the arrangement being such that when the third handle member is gripped together with the first handle member this prevents movement of the arm on which the third handle member is provided relative to the first handle member as the hand tool is lifted.

Certain embodiments also comprise stop means arranged to limit rotation of the first and second pivot members. For example, in certain cases each pivot member comprises a substantially flat lower surface portion, and the stop means is arranged to stop the members in a position in which said flat lower surface portions are substantially co-planar.

The stop means may comprise a stop member attached to and extending from a one of said pivot members and arranged to engage a corresponding engagement surface of the other pivot member. Indeed, the stop means may comprise two stop members, each attached to and extending from a respective one of the pivot members and arranged to engage a corresponding engagement surface of the other pivot member.

In certain alternative embodiments the stop means comprises at least one abutment surface provided on the handle means and arranged to abut a corresponding surface of one of the pivot members. For example, the stop means may comprise two abutment surfaces, each provided on a respective end portion of the handle means and arranged to abut a respective corresponding surface of one of the pivot members.

Certain embodiments also comprise level indication means.

In certain examples the tool further comprises means for adjusting a position of each gripping means on each pivot member, so that blocks of widely differing sizes may be accommodated and gripped.

It will be appreciated that embodiments of the invention address the deficiencies in the known art by providing a safe means of grasping, lifting and transporting loads safely and offers a safe means of carrying loads symmetncally and equally balanced about the body and carrying them at a safe working height while retaining a low centre of gravity.

Brief Description of the Drawings

Embodiments of the invention will now be described with reference to the accompanying drawings, of which: Fig 1. is a perspective view of a hand tool in accordance with a first embodiment of the invention; Fig 2. is a plan view of the first pivoting arm of the tool of fig 1; Fig 3. is a plan view of the second pivoting arm of the tool of fig 1; Fig 4. is a plan view of a gripping member or jaw member of the tool of fig 1; Figs. is a plan view of the handle member of the tool of fig 1; Fig 6. is a perspective view of the spacer from the hand tool of fig 1; Fig 7. is a perspective view of a bush from the hand tool of fig 1; Fig 8. is a perspective view of another bush from the hand tool of fig 1; and Fig 9. is a schematic view of another hand tool embodying the invention.

Fig 10 is a perspective view of another hand tool embodying the invention; and Fig 11 is a side view of yet another embodiment of the invention.

Detailed Description of Embodiments of the Invention Referring now to figures 1-8, a first embodiment of the invention is a hand tool for lifting and carrying building blocks. It can also be used to place those blocks in position during the block laying process. In this example the handle member I is elongated (i.e. relatively long and thin, in the form of a curved bar or arm of generally uniform thickness). This arm 1 is formed from steel, but it will be appreciated that other materials may be used in alternative embodiments. This arm is generally symmetrical about a mid point. The handle is adapted to provide a positive gripping surface (it will be seen on the figure there are undulations on the underside of the bar to locate fingers of a gripping hand, and it extends from a first end 11 to a second end 12. The hand tool also includes a first pivoting member in the form of an arm 2 which extends from a first end 21 to a second end 22, and a second pivoting member 3 also in the form of an arm 3 having a first end 31 and a second end 32. The hand tool is shown in a nominal starting configuration, that is a configuration in which it may be placed over a block in order to then grip and lift the block by lifting the tool via the handle 1. The first and second arms 2, 3 can be described as being in a generally crossed arrangement (in other words a scissorlike arrangement) in that they are coupled together by a generally central pivot means 4.

As the tool is lifted by the handle I each arm 2, 3 is able to rotate in a generally vertical plane about common pivot axis A. It will be appreciated that this rotation is only possible because of the suitably arranged coupling means coupling the handle to the first and second arms 2, 3. In this nominal starting (or engaging) configuration the straight portions of the first and second arms 2, 3 are generally parallel. As the tool is lifted by the handle I the arms rotate about the common pivot such that they are no longer in the parallel configuration.

The pivot means in the embodiment showing fig I comprises a rigid nylon bush 41 received in a corresponding hole 29 in the first arm 2 and an aligned corresponding hole 39 in the second arm 3. In this example the bush 41 has an empty bore 40, but in alternative embodiments a pin or shaft maybe arranged to extend along this bore to increase the strength of the pivot connection. Also, rather than both arms locating on a common, separate bush component, on which they rotate, in alternative embodiments the central pivot means 4 may be provided by a pin or shaft attached to and extending from one of the arms and being received in a corresponding hole in the other.

In this first example, a circular spacer member 42 (which could also be described as a washer member) is also located on the pivot bush 41 (which itself could also be described as shaft means) to space the first and second arms 2, 3 apart on the rotational axis A. The thickness of this spacer member 42 is substantially the same as the uniform thickness of the handle 1. It will therefore be appreciated that when the tool is lifted via the handle the first arm 2 rotates in a generally vertical plane, about pivot axis A, in front of the handle, and the second arm 3 rotates in a substantially vertical plane behind the handle.

At the second ends 22, 32 of each of the first and second arms there is provided respective block gripping means 5 in the form of a generally flat jaw member or gripping member, which could also be described as a claw. Each jaw or gripping member 5 is formed from flat steel sheet in this example and is attached to the respective arm 2, 3 so as to extend downwardly from the arm for engagement with side or end surfaces of a block over which the tool is located. These lower extremities of the jaw members 5 comprise a series of teeth 51 which extend in a direction generally parallel to the rotational axis A so as to provide an extended gripping edge 50. It will be appreciated, however, that in alternative embodiments different shapes and forms of gripping means or jaw members may be used to suit the blocks, bricks, or other components to be lifted. Returning to the present example, each gripping member 5 comprises a rectangular slot 52 whose shape and size corresponds to the cross section of the second ends 22, 32 of the first and second arms. Thus, in manufacturing the hand tool, each gripping member 5 is slotted over its corresponding arm end and secured in place. Various techniques may of course be used. For example, in certain examples the gripping member may be braised or welded in position. In certain embodiments, the jaw member 5 may be arranged to be a sliding fit on the arm. In this case, the jaw members 5 may be slid towards each other on their respective arms to be at a separation suitable for the size of the block (or brick or bricks) to be gripped, and then pins or other suitable members may be inserted in holes 28 provided on the arms to prevent the jaw members 5 from sliding off again. Thus, the position of the gripping means may be adjustable. In the arrangement shown in fig 1, the adjustment holes 28 are provided on both the first and second arms 2, 3 to provide for symmetrical adjustment of the jaw positions relative to the rotational axis A, so enabling the device to be adjusted and still enabling lifting of a block in a vertical direction generally straight up through that block's centre of gravity. In certain alternative embodiments the holes 28 may be used for fixing a level indicator, such as a spirit level, to the arm(s).

The tool shown in fig 1 also comprises first coupling means 112 arranged to couple a first end portion of the handle ito the first arm 2, and second coupling means 123 arranged to couple a second end portion of the handle 1 to the second arm 3. This coupling means is arranged so as to limit the extent to which each arm 2, 3 can rotate about the rotational axis A when lifted by the handle 1. In this example, this is achieved by the first coupling means 112 comprising a rigid bush 102 located in a corresponding circular hole in the first end portion of the handle 1, and extending from the handle I towards the first arm 2. This rigid bush 102 is then received in a suitably sized slot 20 provided in the first end portion of the arm 2. The bush 102 may have a clear bore 10, or alternatively a shaft or pin member maybe provided inside it. The second coupling means 123 has essentially the same construction, with a rigid bush 103 (or shaft means) being fixed in a hole in the second end portion of the handle to extend into a slot 30 providing a first end portion of the second arm. In the nominal starting, or block engaging, position shown in fig 1, the rigid bushes 102, 103 of the first and second coupling means are located at the inner most extremities of the slots 20, 30 with respect to the central pivot. As the hand tool is lifted by the handle 1 the first arm 2 rotates in one direction about the pivot axis A and the second ann 3 rotates in the opposite direction, with the bushes 102, 103 sliding along the respective slots 20, 30 generally outwards from the central pivot. At the same time, the lower gripping edges 50 of the jaw members 5 are urged together, symmetrically (in that they are both urged towards to the general mid plane of the tool, rather than simply one of then been actuated). For suitable lifting, the initial separation of the gripping edges 50 should be such that they engage and grip the end or side surfaces of a block before the rigid bushes 102, 103 reach the outer extremities of the slots 20, 30, because once that position has been reached then further rotation of the arms is not possible. If suitable gripping cannot be initially achieved, then adjustment of the start position of the jaws 5 can be made.

An advantage of limiting the degree of rotation of the arms in this way is that the hand tool is more convenient to carry on its own.

To further facilitate carrying of the hand tool when it is not being used to lift and carry a building block (blocks, brick or bricks), one of the arms (in this case the first arm 2) is provided with a handle member 23. In this example this handle member is attached to the first arm 2 and extends from a position generally proximate the first end of the arm 21 back towards the central pivot, with an end portion of the second handle 23 being generally parallel to the straight portion of the first arm 2. As this end portion of the second handle 23 is close to the central pivot it can be gripped together with the handle I by single hand, so as to hold the components of the hand tool in the general starting (or block engaging) configuration shown in fig 1. Thus, it will be appreciated that in addition to enabling convenient carrying of the hand tool without components moving about, this second handle 23 also enables the jaw members 5 to be held apart in the position shown in fig I, requiring the use of only one hand, so that the hand tool can be brought into position over a block (blocks, brick or bricks) to be lifted. The second handle portion 23 can then be released, and the tool lifted by the handle I alone to grip and lift the object(s).

Advantageously, when a regular block is lifted using the device shown in fig I its centre of gravity is generally directly beneath the centre of the curved handle and the central pivot axis A, so the block is easy to lift and will remain level. Thus the tool can conveniently be used for laying blocks as well as for transportation from one position to another.

Although not shown in the figure, the handle may also comprise a rubber or plastic grip (e.g. a moulded sleeve or cover) over its middle portion, to make the tool more comfortable to lift, and to reduce pressure on the lifting hand.

In the above-described example, the particular bushes 102, 103 and 41 were described as being formed from nylon. In alternative embodiments, steel bushes could be used. Also, it will be appreciated that other materials can be used in further embodiments, and indeed rather than cylindrical bushes, other forms of shaft means could be provided (for example suitable lengths of solid rods or bars).

In the above embodiment, the handle had relatively uniform thickness. However, it will be appreciated that in other embodiments, the handle may have a different shape and/or structure. For example, the handle may comprise a curved tube with minor ripples and/or a rubber grip instead of a flat curved piece of steel with indentations. Other forms may, of course, be used.

Referring now to fig 9, this is a schematic representation of another hand tool embodying the invention. Components of the hand tool corresponding to components to the tool shown in figures 1-8 are given the same reference numbers.

A difference with this second embodiment is that the pivot means 4 is arranged such that the first and second pivoting members or arms 2, 3 pivot about separate respective rotational axes. The first arm 2 pivots about axis A2 and the second arm 3 pivots about axis Al. The handle 1 is again connected to end portions of the first and second arms by respective coupling means. In this example, rather than each coupling means compnsing a pin or shaft means received in a slot, it comprises a rigid coupling member coupled between the respective end of the handle I and the end portion of the respective arm, that end portion of the arm being on the opposite side of the respective pivot axis A from the gripping means or claw 5 provided at the second end of the arm. The coupling means at each end of the handle have the same configuration, and it will be appreciated that, as the coupling means employs a rigid coupling member, hinged between the handle and arm, it permits only a limited range of rotation for each arm about its respective pivot axis. The hand tool is shown with the handle partially lifted, such that the claws 5 are being moved generally towards each other. As with the first embodiment, a block or plurality of blocks or bricks picked up using the hand tool of fig 9 can remain horizontal, which is a distinct advantage for the user and indeed makes the hand tool suitable for both moving and transporting blocks and bricks and for positioning them in place during laying.

Referring now to Fig 10, this shows a lifting tool for lifting construction blocks (including breeze blocks, bricks, stone blocks, concrete blocks) and other such heavy items which is very similar in construction to the embodiment shown in Fig I and described above. Features in common between the embodiment of Fig 10 and the embodiment of Fig I are given the same reference numerals, and will not be described again in detail as the description of them in connection with Fig 1 applies equally. There are some differences between the embodiment of Fig 10 and that of Fig 1, however, as follows. Firstly, rather than the handle member 1 being a unitary component, in the embodiment of Fig 10 it is a composite structure (i.e. an assembly of components) comprising a central portion 13, a first end portion 11 attached by means of a suitable bolt arrangement at one end of the central portion 13, and a second end portion 12 attached to the opposite end of the central portion. This central portion 13 is generally tubular (providing rigidity, yet having low weight), and the middle portion for gripping in a user's hand is substantially thicker than the first and second end portions 11, 12. This makes the tool more comfortable to lift, and also results in lower pressure being exerted on the lifting hand. The connection means between the handle I and the first and second arms again generally comprises shaft means being received within corresponding slots 20 (30 is not visible in the figure) in the ends of these arms to provide a limited degree of rotation of the arms as the device is lifted by the handle. In this embodiment, the shaft means is provided by a bolt 502, nut 501 and washer 503 arrangement, passing through a hole in the respective end portion of the handle, through the slot in the end of the respective arm. Similarly, the central pivot between the first and second arms comprises a bolt 43, washer 44, and nut (not shown) arrangement passing through holes in those arms and through the central spacer 42. In the embodiment of Fig 1, only one of the arms was provided with an additional handle member 23. In contrast, in the embodiment of Fig 10 each arm is provided with a respective additional handle member 23, 33 and when the device is lowered onto a flat surface the handle means I and both of these additional handle members 23, 33 can be gripped in a single hand to prevent rotation of the arms 2, 3. The tool can then be moved around and positioned over a block or brick (or a plurality thereof). The embodiment of Fig 10 includes an additional feature in the form of stop means 70 arranged to limit rotation of the first and second arms about their common rotational axis A when the tool is lowered onto a flat surface. In other words, the stop means 70 defines a resting, or stop position for the two arms. In this embodiment the stop means 70 comprises a pair of stop assemblies, each attached to and extending laterally from a respective one of the pivoting arms 2, 3. Each stop assembly comprises a bolt 72, a collar 73, and nut 71. The bolt 72 passes through the collar 73 and through a corresponding hole provided in the respective arm 2, 3 and is then secured in place with the respective nut 71. As will be appreciated from the figure, as the apparatus is lowered onto a flat surface (so that the gripping surfaces 50 of the claws 5 come into contact with that flat surface) the arms 2, 3 will rotate about the axis A until stopped by the stop means 70. In this stopped position an engagement surface 307 of the second arm 3 rests against the rubber collar 73 of the stop means 70 provided on the firstarm 2, and a corresponding engagement surface 207 of the first arm 2 rests on the collar 73 of the stop means 70 extending laterally from the second arm 3. Thus, in this embodiment, which incorporates a spacer 42 between the arms 2, 3, mechanical stops are provided on which the arms rest when the hand grip is released. This prevents the arms from hitting the bolt heads 502.

Also, the attachment between the central portion 13 of the handle and each of the end portions 11, 12 is adjustable Referring now to Fig 11, this shows yet another embodiment of the invention. In this embodiment the handle 1 is a one-piece nylon component having a relatively thick central portion 13 and relatively thin end portions 11, 12.

Laterally extending shafts 102, 103 are attached to the handle and are received in respective slots 20 (30 not shown) in the ends of the pivoting arms 2, 3. In this embodiment there is no spacer between the pivoting arms 2, 3. The apparatus includes stop means, but rather than this being provided by stop members (e.g. assemblies) on the sides of the pivoting arms themselves, the stop means is provided by abutment surfaces 142, 143 on the handle member which, in the stop position shown in Fig 11, abut corresponding surfaces (upper surfaces) 207 and 307 on the first and second arms and so limit rotation of those arms in one direction (that direction being anti-clockwise for the first arm 2 as viewed in the figure and clockwise for the second arm 3). The pivot means between the first and second arms is again provided by a bolt 43, washer 44 and nut (not shown) arrangement. In this embodiment, the first arm 2 comprises a substantially flat lower surface 200 and the second arm 3 also comprises a substantially flat lower surface 300. The stop means in the form of the abutment surfaces 142, 143 of the handle I is arranged to stop the components in the position shown in Fig 11 when the apparatus is lowered on to a flat surface (or indeed over the top of a block having a flat upper surface) with the flat lower surfaces 200, 300 substantially in alignment (i.e. co-planar).

S This embodiment also comprises level indication means 800, which in this example comprises a spirit level attached to one of the pivoting arms 2. The lifting apparatus can therefore be positioned on a block with the surfaces 200, 300 co-planar and in contact with a flat upper surface of the block. The apparatus can then be lifted via the handle I with the sides of the block being gripped by the claws or gripping members 5. The block can then be lifted and transported to a position in which it is to be laid. Then, with the tool again being rested on the upper surface of the block the level indication means 800 can be inspected to determine whether the orientation of the block is true. Although a spirit level for determining correct horizontal alignment is shown in the figure, it will be appreciated that in other embodiment's alternative or additional level indication means may be used, so that a correct vertical orientation of the block may alternatively or additionally be determined. Another difference between the embodiment of Fig II and previous embodiments is that the additional handle member 23 provided on the first arm 2 is curved (i.e. generally arcuate) and is attached at either end to the pivoting arm 2.

The curve of this additional handle 23 generally conforms to the shape of the curved main handle 1 and so facilitates the gripping together of these two handles with a single hand for transporting and or positioning the apparatus. Thus, in the embodiment of fig. lithe tool incorporates a moulded nylon handle 1 in which the handle section is expanded in thickness below the pivots 102, with a stop moulded into it. The second handle member 23 forms an arc parallel to the main handle.

From the above description it will be appreciated that, in certain embodiments, the arrangement of the components is such that when the hand tool is lowered by the handle member, a first arm and a second arm lie parallel to each other and in contact with the top surface of an object being carried or that had been previously placed or positioned. The tool may then facilitate an appraisal of the object's degree of plumb (horizontally and/or verticality) by incorporating a level indication means, e.g. in the form of a spirit level or equivalent device, attached to any part of the hand tool.

The level indication means could, for example, be a single instrument enabling an appraisal or reading of information relating to both horizontal and vertical axes It will be appreciated from the above that embodiments of the invention provide the following advantages. The hand tool may be self-levelling in the hand. A standard building block can be lifted using a hand tool embodying the invention, and also can be lowering into position during laying. Rather than just a single block, two or more blocks can be lifted and lowered with a hand tool embodying the invention, provided the separation of the gripping jaws is suitable with respect to the dimensions of the blocks. In certain embodiments, the separation of the gripping or jaw members can be adjustable. This can be achieved by means of providing means for adjusting the positions of the jaw members on the arms, or indeed the lengths of the arms themselves may be adjustable. Clearly, in order to support the weight of a block gripped by the hand tool, a user must apply an upward force to the handle equal to the weight of the lifted block plus the weight of the device itself. By means of the coupling between the handle and the pivoting arms, this force results in a large gripping force being applied to the side or end surfaces of the gripped block.

In effect, the weight of the lifted component assists in its gripping. By enabling blocks to be lifted vertically through their centres of gravity, hand tools embodying the invention thus provide safe lifting means, reducing the risk of injury to workers in the building field. By actuating the gripping means on either side of the block symmetrically and simultaneously, embodiments of the invention enable objects to be lifted safely with reduced risk of damage to the lifted objects. Using two hand tools embodying the invention, a worker is able to carry an equal load in each hand, with a total load that is held symmetrically about the body, again reducing risk of injury.

Embodiments of the invention may also be used for the safe lifting and lowering of concrete and stone curb blocks, edgings, and other heavy objects. In use, hand tools embodying the invention may also be used to lift and carry and lower one or more bricks or blocks prepared with mortar for building walls and structures of various kinds.

Certain embodiments of the invention maybe provided with level indication means to assist in the process of building walls and other structures accurately. This level indication means may, for example, be in the form of a spirit level.

Claims

Claims 1. A hand tool for lifting and carrying building blocks,

comprising: a generally elongate handle member having a first end and a second end; a first pivoting member; a second pivoting member; first coupling means arranged to couple a first end portion of the handle member to the first pivoting member; second coupling means arranged to couple a second end portion of the handle member to the second pivoting member; pivot means arranged to couple the first pivoting member to the second pivoting member such that each member can rotate in a substantially vertical place about a substantially horizontal pivot axis when the hand tool is lifted by the handle member, and wherein each of the first and second pivoting members comprises a respective gripping means for engaging and gripping a surface of a block to be lifted by the hand tool, the arrangement being such that when the hand tool is lifted by the handle member, the first and second pivoting members are urged to rotate such that the gripping means are urged together, whereby a block positioned between the gripping means may be gripped and lifted.
2. A hand tool in accordance with claim I wherein the handle member is generally arcuate.
3. A hand tool in accordance with claim I or claim 2 wherein the handle member comprises a rigid bar or arm.
4. A hand tool in accordance with any preceding claim wherein the pivot means is arranged such that the first pivoting member and second pivoting member rotate about a common pivot axis.
5. A hand tool in accordance with claim 4, wherein the pivot means comprises shaft means received in a hole in the first pivoting member and in a corresponding hole in the second pivoting member.
6. A hand tool in accordance with any preceding claim wherein the first pivoting member comprises a first arm having a first end and a second end, and the second pivoting member comprises a second arm having a respective first end and second end.
7. A hand tool in accordance with claim 6, wherein said first and second arms are arranged in crossed relationship to each other.
8. A hand tool in accordance with claim 7, wherein the pivot means is arranged such that a point at which the arms cross is fixed and corresponds to a common pivot axis about which the first arm and the second arm can rotate.
9. A hand tool in accordance with any one of claims 6 to 8, wherein the first coupling means couples the first end portion of the handle means to a first end portion of the first arm and the second coupling means couples the second end portion of the handle means to a first end portion of the second arm.
10. A hand tool in accordance with any one of claims 6 to 9, wherein the respective gripping means of each arm is provided at the second end of each arm.
11. A hand tool in accordance with claim 10, wherein the gripping means of each arm is arranged to extend generally downwards from the second end of the respective arm when the hand tool is lifted by the handle means.
12. A hand tool in accordance with any one of claims 10 or 11, wherein the respective gripping means of each arm is arranged to provide a gripping surface which extends in a direction generally parallel to the rotational axis of each ann.
13. A hand tool in accordance with any one of claims 6 to 12, further comprising a spacer member arranged between the first and second arms to separate them in a direction parallel to the pivot axis.
14. A hand tool in accordance with claim 13, wherein the handle member has a substantially uniform thickness in a direction parallel to the pivot axis, and said handle thickness is substantially equal to a thickness of the spacer member in a direction parallel to the pivot axis.
15. A hand tool in accordance with any preceding claim, wherein the arrangement is such that when the hand tool is lifted by the handle member, the first pivoting member is arranged to rotate in a vertical plane on one side of the handle member and the second pivoting member is arranged to rotate in a vertical plane on the other side of the handle member.
16. A hand tool in accordance with any one of claims I to 13, wherein the handle member comprises a central portion, the central portion being substantially thicker than the first and second end portions of the handle member in a direction parallel to the pivot axis.
17. A hand tool in accordance with any preceding claim, wherein the first coupling means comprises shaft means attached to and extending from one of the handle member and first pivoting member, the shaft means being received in a slot provided in the other one of the handle member and first pivoting member.
18. A hand tool in accordance with claim 17, wherein said slot is arranged to permit limited rotation of the first pivoting member as the hand tool is lifted by the handle member.
19. A hand tool in accordance with any preceding claim, wherein the second coupling means comprises shaft means attached to and extending from one of the handle member and the second pivoting member, the shaft means being received in a slot provided in the other one of the handle member and second pivoting member.
20. A hand tool in accordance with claim 19, wherein the slot of the second coupling means is arranged to pen-nit limited rotation of the second pivoting member as the hand tool is lifted by the handle member.
21. A hand tool in accordance with any preceding claim, further comprising a second handle member provided on one of the first and second pivoting members, the second handle member being positioned such that it can be gripped together with the first handle member by a single hand, the arrangement being such that when the second handle member is gripped together with the first handle member this prevents movement of the arm on which the second handle member is provided relative to the first handle member as the hand tool is lifted.
22. A hand tool in accordance with claim 21, further comprising a third handle member provided on the other one of the first and second pivoting members, the third handle member being positioned such that it can be gripped together with the first handle member and the second handle member by a single hand, the arrangement being such that when the third handle member is gripped together with the first handle member this prevents movement of the arm on which the third handle member is provided relative to the first handle member as the hand tool is lifted.
23. A hand tool in accordance with any preceding claim, further comprising stop means arranged to limit rotation of the first and second pivot members.
24. A hand tool in accordance with claim 23, wherein each pivot member comprises a respective substantially flat lower surface portion, and the stop means is arranged to stop the members in a position in which said flat lower surface portions are substantially co-planar.
25. A hand tool in accordance with claim 23 or claim 24, wherein the stop means comprises a stop member attached to and extending from a one of said pivot members and arranged to engage a corresponding engagement surface of the other pivot member.
26. A hand tool in accordance with claim 25, wherein the stop means comprises two stop members, each attached to and extending from a respective one of said pivot members and arranged to engage a corresponding engagement surface of the other pivot member.
27. A hand tool in accordance with claim 23 or claim 24, wherein the stop means comprises at least one abutment surface provided on the handle means and arranged to abut a corresponding surface of one of the pivot members.
28. A hand tool in accordance with claim 27, wherein the stop means comprises two abutment surfaces, each provided on a respective end portion of the handle means and arranged to abut a respective corresponding surface of one of the pivot members.
29. A hand tool in accordance with any preceding claim, further comprising level indication means.
30. A hand tool in accordance with any preceding claim, further comprising means for adjusting a position of each gripping means on each pivot member.
31. A hand tool substantially as hereinbefore described with reference to the accompanying drawings.