A hand pallet truck and a method for its manufacturing In order to handle load pallets with their load in lorries, shops etc so called hand pallet trucks (or just hand trucks) are frequently used. These are constituted by lifting load forks that in their rear end are connected with a hood (often called A-frame) to a frame. Below the front end of the forks support rollers are arranged and in the head end steer wheels are arranged mechanically connected to the support rollers so that wheels and rollers together, by a lifting cylinder arranged between steer wheel and hood, can lift the frame and the forks together with goods thereon. The lifting cylinder is at this a part of a jack device that for the lifting of the frame is connected with a tiller, with which the steer wheels can be turned relative the frame. For the lowering and placing of the load on the floor there is a valve arrangement for relieving the hydraulic pressure in the lifting cylinder.

These hand pallet trucks are well known since long (half a century). The concept has been copied world wide and hand pallet trucks of this type are each year sold in great numbers. Due to competition there exist and has always existed a wish to manufacture the hand pallet trucks at lower costs. Despite the existence of this wish for many years the hand pallet trucks have remained principally unchanged over decades. The present embodiment does thus seem to be optimal and the possibilities to improve these hand pallet trucks seem to be minimal.

Even if the known hand pallet truck is optimal from most viewpoints it has one drawback, it is comparatively bulky. This means that the transport cost will constitute a non-neglectable part of the price for a consumer or user. This problem becomes particularly obvious at long transports and it is therefor known to distribute the hand pallet trucks in units that are then assembled locally by personnel of different sales companies. A number of frames are stacked on top of each other and a corresponding number of the remaining components are separately packed. In this way the parts of a number of hand pallet trucks can be packed and transported more economically on different pallets or the like. A drawback at this is however that the optimal transport requires a certain number of hand pallet trucks each time in order for the frames as well as the remaining parts to fill up the related transport spaces. This results in an undesired storing alternating with no trucks in store.

A second drawback with the distribution in parts is the need to have specially trained personnel for the assembly of the hand pallet trucks. Since this personnel and their available shop resources is not specialized in the same manner as at a manufacturer this assembly will not be as efficient and even if transport costs are reduced the work cost increases. A result is frequently also

that one has to wait for a particular person to have time to assembly the hand pallet truck, something that the customer may consider as bad service. At locations with low sales the transport costs increase the price.

There exist thus since many years back a need for an improved distribution of hand pallet trucks.

The object of the invention is to solve this problem, which is achieved by the hand pallet truck being distributed in optimally separated units that then are assembled at a suitable location in the transport chain, either at the retailer or the user-buyer. In order to make this possible the structure of the hand pallet truck is changed so that the frame constituted of the forks and the hood is delivered in two units, the forks and the hood, which units are then assembled either at a sales company, a retailer or indeed at the user-buyer.

In a further development of the inventive thought one can consider to arrange the pivot axle of the rocker levers, that control the lifting movement of the steer wheels, in the forks or the part bridging these. In this way it becomes possible to preassemble the mechanics of the support rolls including these already at the manufacturer and at a later assembly essentially only three units are assembled, namely: the forks, the hood and the hydraulics including tiller and support wheel. These three units can be packed together in one common package that with a bottom area essentially corresponding to that of the forks is only 20cm high containing all the parts that are needed for the complete hand pallet truck. This means that the hand pallet truck can be packed, transported and distributed more rationally and without disadvantages in any desired number.

By in accordance with the invention allowing the hand pallet truck be constituted of the three mentioned units also the assembly in itself becomes simple and can by two persons (appropriate from weight reasons, since the hand pallet truck in its entirety weighs almost 90 kilograms) be assembled in 20 minutes. The assembly is further so simplified that a minimum of tools are needed and anybody can assembly the hand pallet truck. Nor is any final adjustment of the valve control or other parts required. Instead this can be carried out professionally at the manufacturer with the aid of proper fixtures etc. This in turn means that the hand pallet truck can be sent to and assembled by the consumer, resulting in an additionally lowered cost. Since tiller and hydraulics are delivered assembled there is no risk of damages caused be unintentional releasing of the comparatively powerful spring that lifts the tiller upwards.

Further advantages and characteristics of the invention are apparent from the claims as well as from the following description of a preferred embodiment with reference to the

accompanying drawings. In the drawings fig 1 schematically shows the frame of the hand pallet truck in assembled state, fig 2 the forks with some parts mounted, fig 3 a longitudinal section of a part of the hand pallet truck, fig 4 a packing scheme for the hand pallet truck, and fig 5 an exploded view of the hand pallet truck according to the invention.

The hand pallet truck shown in the drawings include a hood 22 (A-frame) that by means of bolts 19 is fastened to the forks 23, that in their rear ends are joined by a bridge part 24 to a fork unit. In said ears 21 a pivot axle 25 is journaled and on said pivot axle two rocker levers 15 are fixed. The rocker levers 15 are by means of two lever bolts 16 hingedly connected to a lower thrust plate 14.

The rocker levers 15 extends with downwards angled parts further downwards below the support surface of the forks and the angled parts are there via bolts 27 hingedly connected to push rods 26 that inside the forks extend forwards to support rolls (not shown) in the front ends of the forks.

A central hole is arranged in the thrust plate 14 and through this hole a steering axle 28 extends. In the lower end of the steering axle a pair 29 of steer wheels are arranged. In the upper end the steering axle 28 is connected to a hydraulic cylinder 30 that can press against the lower thrust plate 14. The hydraulic cylinder has an upper thrust plate 12 arranged in the top 13 of the hood 22.

A tiller 1 is further joined to the hydraulic cylinder. The tiller is pivotable up an down and at this influence a small hydraulic cylinder 31. A spring 32 surrounding the small cylinder lifts at rest the tiller to a vertical upright position. The small hydraulic cylinder 31 is connected to the larger hydraulic cylinder in such a way that a lift jack construction is obtained. By a pumping action with the tiller 1 the larger hydraulic cylinder 30 can thus press the piston and thereby the upper thrust plate 12 upwards. This result in the hood being pressed upwards. The movement downwards for the support wheels concurrently result in a swing movement for the rocker levers 15, which in turn give the downwards angled parts a movement downwards. This movement act on the push rods 26 resulting in a corresponding movement downwards for the support rolls arranged in the front end of the hand pallet truck. The lengths of the levers are calculated to move the forks at a lifting or lowering movement entirely parallel to the ground.

In order to return the forks to a lower position after a lifting a valve device, spring loaded towards a closed position, is arranged to allow a return flow from the large lifting cylinder 30.

This valve may either be influenced via a manoeuver means in the handle or via a pedal 9.

The hand pallet truck is steered by the turning of the tiller laterally in relation to forks and hood, at which the larger hydraulic cylinder 30 turns together with the steer wheels journaled via the axle going through the thrust plate and a turning movement in the thrust plate 12 in the top 13 of the hood.

At delivery the above hand pallet truck is delivered in a box lying in for instance the way that is shown in fig 4. The entire mechanics of the front rolls including push rods and rocker levers 15 are here already mounted in the forks. The hood contains no moveable parts and is free from the forks. The entire hydraulics and tiller package constitute one unit.

When assembled the hood is mounted on the forks with the bolts 19. The forks are preferably provided with bolts or the like welded to the inside so that one only have to tighten the bolts from the outside. Alternatively so called coach bolts can be used that is inserted into square holes while nuts are mounted on the inside, which version has the advantage of a smother outside, at the same time as the assembly becomes somewhat more difficult. Then the thrust plate 12 is inserted into the top 13 of the hood and the rocker levers 15 are fastened pivotably journaled to the thrust plate 14 by means of the arm bolts 16.

This embodiment of the invention requires, as apparent from the above description, in addition to the three main units in the box only six additional bolts (19 and 16), which without difficultly may be so designed that they are impossible to mount in the wrong place. The measures needed at mounting are very few and the assembly is simple and even simple to describe.

The hand pallet truck according to the invention may if so is desired be transported to for instance sales companies in smaller units alternatively it can be separated in other ways than the one described above. For instance one can consider the rocker levers with their axle being joumaled in the hood in the known manner. Here it becomes necessary to mount the push rods to the angled parts of the rocker levers.

One can also consider the hood instead of being fastened in its entirety to forks to be divided above the rocker lever bearings. This is however from an aesthetic point of view less appealing.

The connection of forks and hood may within the frame of the invention be achieved in different ways and may include such varieties as the insertion of the forks into the hood, which also may allow the advantage of locating the bolts at the bottom for the forks and/or on the side facing away from the forks. This however requires if the rocker levers and their j oumaling are

still intended to remain in the forks that the hood has a front opening allowing it to be pushed over these parts. The opening may then be closed. Alternatively one can as has been mentioned above consider journaling the rocker levers in the hood, which however result in the push rods having to be connected at the final assembly.

Also the front side towards the fork and the load facing side can be used for bolting to the bridge 24 connecting the forks. The design with bolts on the front and rear side of the hood but not on its lateral panels may also give the advantage with entirely smooth side edges without increase in cost.

As apparent from the above the manufacturing and distribution of the known hand pallet truck has become considerably simpler and more efficient through the invention. At the dis- tribution to sale companies with final assembly the number of assembly steps has been reduced simultaneously with an improvement in the choice of number and packing volume. If so desired also the possibility with delivery directly to a user has been accomplished with a very simple although heavy kit. It should be mentioned that the hand pallet truck according to the invention also is possible for one person to assembly, at which a certain blocking up of the units will be necessary. The flexibility increase in this way and it is no longer necessary to have a sales company close by since the kit can be delivered anywhere, even directly from the manufacturer if so is desired.

Within the inventive thought one can also locate and shape the ears for the rocker lever axle so that the bolting of the hood may be directly in these.

Possibly within the inventive thought the hand pallet truck with its different mechanical parts may be folded in the normally existing joints at the transport from the manufacturer to user or sales companies and then the only measure required at arrival is that the parts are unfolded up to their intended working positions and the hood is mounted locking the working position. For instance the hood may at this include rocker lever bearings, and possibly also the links mounted on these.

An essential advantage of the invention is that all adjustments can be carried out already at the manufacturer at the first assembly and no final adjustment, as has previously been required, is necessary at the final assembly. This is necessary in order to allow any buyer to do the final assembly himself. Nor is there any risk of the person doing the final assembly being injured by the spring that swing up the tiller.