The present invention relates to a cart or trolley, and more specifically to a so-called sack or bag cart which comprises two wheels which support a frame structure having a handle at the top thereof and an insert or ledge at the bottom thereof.

One problem with conventional sack or bag carts is that the tongue located at the bottom of the frame structure and intended for insertion beneath the load to be trans¬ ferred onto the cart must be sufficiently small to enable the tongue to be inserted beneath the load. However, when this condition is met the tongue is then too small to enable the load to be transferred reliably onto the cart and be held securely on the cart with the aid of the tongue. Another drawback with carts of this kind is that they cannot be used readily for lifting loads from pallets. The use of pallets in material- handling systems is becoming more and more usual, there¬ with increasing the need for auxiliaries by means of which loads can be lifted from the pallets.

When transferring the load located at the pallet edge over to the cart, it is necessary, when using conven¬ tional carts, to lift the cart so that the tongue is level with the upper surface of the pallet, and then hold the cart lifted in this position while, at the same time, endeavouring to force the tongue in beneath the load to be lifted. When the tongue has ultimately been inserted beneath the load, there is no counterpressure- surface on which the wheels are able to bear when endea¬ vouring to tip up the cart, and the cart simply hangs in space, meaning that attempts must be made to hold the load on the cart by hand while, at the same time, endea¬ vouring to lower the loaded cart onto the floor.

An object of the present invention is to avoid the aforesaid problems. This object is achieved with a cart of the kind defined in the Claims and having the charac¬ teristic features set forth therein.

The invention will now be described in more detail with reference to the accompanying drawings, in which FIGURE 1 is a perspective, front view of an inventive cart; FIGURE 2 is a partially broken-away and partially sec¬ tioned side view of the cart shown in Figure

1; FIGURE 3 is a partially broken-away and partially sec¬ tioned side view of the cart in Figure 1, and shows a first step of a load-lifting opera¬ tion? FIGURE 4 is a partially broken-away and partially sec¬ tioned side view of the cart shown in Figure 1, and shows the beginning of a second step of a load-lifting operation;

FIGURE 5 is a partially broken-away and partially sec¬ tioned side view of the cart shown in Figure 1, and shows the cart subseguent to completion of the second step of a load-lifting opera- tion;

FIGURE 6 is a partially sectioned, broken-away schemat¬ ic side view of an alternative cart-lifting mechanism, and shows the cart in a rest posi¬ tion; and FIGURE 7 is a view corresponding to Figure 6 and shows the cart in a lifting position with the tongue outwardly extended.

The cart or trolley 1 shown in Figure 1 comprises a frame structure 2 of a generally rectangular configura¬ tion when seen from the front and a pair of wheels 3

which are journalled on the bottom frame. A slide 4 is mounted on the frame structure 2 in a manner to enable the slide to be moved there along. The slide 4 is pro¬ vided at its lower end with a raisable and lowerable tongue or ledge 5, which projects outwardly and forward- ly from the frame structure 2 through a short distance. A displaceable further tongue or ledge 6 is also mounted on the slide 4 immediately beneath the raisable and lowerable tongue 5. This further tongue 6 can be moved between a position in which it extends outwardly through an appreciable distance in front of the raisable and lowerable tongue 5 and a second position in which said further tongue is withdrawn and lies behind the raisable and lowerable tongue 5.

Mounted on the lower end of the frame structure 2 is a pair of support or back-up wheels 7 which enable the cart 1, which is normally rested in an upstanding, slightly rearwardly inclined position, as shown in Figure l, to stand firmly on the four wheels 3 and 7 without requiring any further assistance. This wheel arrangement is conventional and does not form any part of the invention.

In the case of the illustrated and described embodiment of the inventive cart 1, the frame structure 2 is com¬ prised of two essentially identical tubular side-pieces 8, 9 which have a straight extension from the respective attachments 10 for wheels 7, up to a rearwardly-down- wardly curved handle-part 11 and back to the straight parts of respective side-pieces or tubes 8, 9. The wheels 3 are journalled at each end of an axle 12 which extends parallel with the general plane of the essen¬ tially rectangular frame 2, but which is displaced rearwardly therefrom, at which location it is attached to a tube 13 which extends rearwardly from respective

wheel attachments 10. A further tube 14 extends from the end of the curved handle-part 11 and also from the rear side of the straight part of the tubes 8, 9, down to the axle 12. A fixed cross-piece 15 extends between the respective upper end of the straight parts of respective tubes 8, 9.

The slide 4 is comprised of two tubes 16 which are oveably mounted on the tubes 8 and 9 and which can be moved between a raised position, shown in Figure 1, and a lowered position, shown in Figure 2. The tubes 16 are connected at their upper ends by means of a transverse member 18. A rail or bar 19 extends from the transverse member 18 to a transverse guide 20 which has an operat- ing device fastened to the rear side thereof. Attached to the rear side of the cross-member 15 is a pivotal handle 17 which is connected to the slide 4 by means of a transmission means (not shown), wherein the slide 4 is raised up in one terminal position of the handle, as shown in Figure 1, and is lowered in the other terminal position of said handle, as shown in Figure 2. In the terminal position of the slide 4, shown in Figure 1, the cart 1 is adapted for use in the near proximity of a pallet, since the tongues are then essentially level with the upper surface of the pallet.

Attached to the lower part of the slide 4 is a pair of short, mutually opposing tubes 21 which lie inwardly of the slide and which are mutually connected by means of a cross-brace 22 at their bottom ends. Extending from the cross-brace 22 is a rod 23 (not shown fully) which coacts with the handle 17 for adjusting the height of the slide 4. A pair of axially-moveable rods 24 extend through the tubes 21 and the upper ends of the rods are connected through a further cross-brace 25 and the raisable and lowerable tongue 5 is attached to the lower

ends of these further rods 24. Extending from the cross- brace 25 is a rod 26 which coacts with a pivotal handle 27 on the rear side of the transverse guide 20. The raisable and lowerable tongue 5 is raised and lowered between the positions shown in full lines and broken lines respectively in Figure 3, by commensurate swinging of the handle 27.

Figure 5 shows the cart with the tongues 5 and 6 in their lower positions and with the displaceable tongue 6 in an outwardly displaced position. Mounted on the rear side of the slide 4 and projecting out towards the wheels 3 is an upper guide 30 which has an elongated guide channel 31 that extends generally parallel with the frame tubes 8 and 9, and a lower guide 32 which is provided with an arcuate channel 33 and which extends rearwardly and upwardly at an acute angle in relation to the frame tubes 8, 9. A bar or brace 34 connects the outer end of the guide 32 with the tubular member 16 of the slide, so as to strengthen the guide 32. The bottom ends of a pair of rails 35 are attached to that part of the tongue 6 which is located on the rear side of the frame 2. These rails 35 extend upwards adjacent the guides 30 and 32 respectively and are provided with guide pins 36, 37 which run in tracks 31 and 33 in respective guides 30 and 32. A rod 38 extends from the rear part of the displaceable tongue 6 to a pivotal handle 39 on the rear side of the transverse guide 20. When the handle 39 is swung upwards, the displaceable tongue 6 is guided through the coaction between the tracks 31 and 33 in respective guides 30 and 32 and the guide pins 36 and 37 in the rails 35 in a manner to draw the displaceable tongue back to the position shown in Figures 3 and 4, whereas when the handle 39 is swung downwards, the displaceable tongue 6 is guided to the

outwardly extending position shown in Figures 1, 2 and 5.

Because the handles 27 and 39 are mounted on the trans- verse guide 20, which accompanies movement of the slide 4, the two tongues 5 and 6 can be manoeuvered indepen¬ dently of the position of the slide 4. Although in the case of the illustrated and described embodiment of the invention, movement of the slide 4 and of the tongues 5, 6 is effected with the aid of rods and pivotal handles, it will be understood that such movement can also be achieved in other ways, for instance with the aid of hydraulic transmissions and with the use of pedals instead of handles.

The inventive cart 1 operates in the following manner:

In the starting position of the cart, the displaceable tongue 6 is withdrawn to the position illustrated in Figure 3. This Figure also shows the raisable and lower¬ able tongue 5 in the position taken by the tongue when the slide 4 is in its lower position. It will be under¬ stood, however, that the function is the same when the slide 4 occupies its upper position, which is adapted so that the tongue 5 can then be inserted between a load and the upper surface of a pallet.

The raisable and lowerable tongue 5 which, in the full- line position shown in Figure 2, is first pressed in between the supporting surface, e.g. a floor 40, and the object to be transferred to the cart 1, in this case a carton or box, in a manner conventional with this type of cart. Because the tongue 5 is relatively thin and only extends a short distance outwardly from the frame 2, the tongue can be pressed in between the load and the cart-supporting surface relatively easily, although the

tongue is normally too small to subsequently hold the load securely on the cart. Subsequent to having pressed the tongue 5 to the position illustrated in full lines in Figure 1, the cart operator moves the tongue upwards to the position shown in broken lines, therewith raising the tongue some few centimeters. However, this is suffi¬ cient to lift the load 41 slightly away from the cart- supporting surface and thereby provide a gap 42 between load and supporting surface.

In this position of the cart, the cart operator swings down the handle 39 and forces the tongue 6 into the gap 42, as shown in Figure 4. When the tongue 6 has been extended to a maximum extent, the operator lowers the raisable and lowerable tongue 5 into abutment with the tongue 6, whereafter the operator tips back the cart 1, in a conventional manner, so that the load will rest against the frame 2 and be held by the tongues 5 and 6.

Figure 6 illustrates a cart arrangement 100 with the cart returned to its rest position. The arrangement 100 is journalled on two mutually parallel and mutual iden¬ tical brackets 102, 102' (of which only the distal bracket 102 is shown in the Figure). The brackets 102, 102' are attached to cross-braces 103 which mutually connect the two tubular frame-walls 104, 104' of a cart (of which walls only a part of the distal wall 104 is shown in the drawing) . A lever 105 and a rocker arm 106 are pivotally mounted between the brackets 102, 102' by means of pivots 107, 108.

A foot pedal 151 is mounted on the end of the lever 105 which faces towards the operator, i.e. on the rear side of the cart, while mounted on the opposite end of the lever, i.e. on the front side of the cart, is a rotat- ably journalled roller or runner 152 and a pivot journal

153 which is located at a radial, angular distance from the roller 152 and mounted in a pivot lug.

Mounted on the end of the rocker arm 106 extending towards the rear side of the cart is a pivot journal 161 and a U-shaped guide track 162 which is mounted symmet¬ rically beneath the pivot pin 108 and which has two shorter, generally vertical track parts and a longer, connecting horizontal track-part which accommodates an arcuate pressure spring 163. The rocker arm 106 also includes a pin 164 which coacts with a torsion spring 121 mounted on one of the aforesaid brackets 102, 102'. In the aforesaid rest position, the torsion spring 121 carries the weight of the rocker arm 106 and holds the arm in a generally horizontal position, as shown in Figure 6.

Pivotally mounted in the pivot journal 153 of the lever 105 is a pressure rod 154 which alternately engages the two vertical track-parts of the U-shaped track 162, through the medium of a guide pin 155.

Pivotally attached to the pivot journal 161 of the rocker arm 106 is a further pressure rod 165 which is pivotally connected to a load-bearing link 109, through the medium of a guide pin 166. In order to enable the link 109 to pendulate, the guide pin 166 is journalled in an elongated guide track 143 formed in a guide rail 141 which is mounted on the tubular frame wall 104, in the plane thereof, and which slopes slightly forwards/ downwards in relation to the horizontal plane.

The link 109 has provided at the bottom end thereof a forwardly extending tongue or ledge 191 on which the goods to be transported rest, or rests, in the working position of the cart. Provided on the upper end of the

link 109 is a pivotal pin 192 which is displaceably journalled in a guide track 144 provided in a guide rail 142 which is mounted in the tubular frame wall 104 and located in the same plane as said wall. The guide track 144 is also inclined forwardly/downwardly in relation to the horizontal plane, but forms a more obtuse angle with said plane than the angle formed by the guide track 143. Because the pivot pin 192 is journalled in the guide track 144, the link 109 has a moveable swinging centre, whereby the tongue 191 is caused to move generally linearly when moved forwards during transportation of goods.

Two tubes 145, 145' (of which only the distal tube 145 is shown in Figure 6) are attached to the bottom part of the two forward frame tubes on the tubular frame wall 104, and on the inner surfaces of said two frame tubes. The two tubes 145, 145' form guides for the round rods 146, 146' displaceably mounted in the tubes (of which rods only the rod 146 is shown in Figure 6). The upper ends of the rods 146, 146' are connected to the cross brace 147, while the bottom ends of the rods are con¬ nected to the tongue 148. A narrow tongue 149 is dis¬ placeably mounted on the outside of the tubular frame wall 104 shown in Figure 6, said tongue 149 being rais¬ able and lowerable by means of a lever (not shown) on the outside of the frame tube, through the medium of a lifting and lowering line, also not shown.

Mounted on the rear side of the cross-brace 147, at the lower edge thereof, is a shoulder 140 which is located centrally opposite the roller 152 and which presents to the roller 152 a concave surface whose centre of radius lies in the pivot pin 107.

The arrangement also includes a pull spring 122 which

acts between the bracket 102 and the lever 105, so as to return the lever, and therewith the pressure rod 154, in said rest position, to a position (illustrated in chain lines in Figure 6) in which the lever and rod can again be manoeuvered to forwardly extend the tongue 191.

Manoeuvering of the arrangement and lifting of a load resting on the tongues of the cart is effected in the following manner, starting from the rest position shown in Figure 6 (by rest position is meant the position in which the lever 105, the pressure rod 154, the tongue 148 and the round rods 146 and cross-brace 14) coacting therewith occupy the positions shown in chain lines):

The tongue 149 is inserted beneath one corner of the load to be transported by the cart, whereafter the load is lifted at this corner with the aid of the hoist line and lever (not shown) in coaction with the tongue.

The tongue 148 is then inserted simply beneath one side edge of the load, or object:

Downward/forward pressure is then exerted on the pedal 151, so as to rotate the lever 105 around the pivot pin 107, wherein the roller 152 presses against the bottom edge of the cross-brace 147 and lifts the brace and therewith also the round rods 146 and the tongue 148 connected to the cross-brace. When the transportation object has been lifted sufficiently for the tongue 191 to be inserted beneath the bottom of said object, the roller 152 rolls away from the bottom edge of the cross- brace and out onto the concave surface of the shoulder 140, during continued rotation of the lever 105. Because the curvature on the shoulder has a radius whose centre is coincident with the centre of the pivot pin 107, no further raising of the cross-brace 147 or of the element

connected thereto will take place, despite continued pendulation of the lever 105.

As the lever 105 pendulates, the pressure rod 154 moves the rocker arm 106 to the position shown in Figure 7, wherein the guide pin 155 engages the forward vertical part of the U-shaped guide track 162.

The pendulating movement of the rocker arm 106 around the pivot pin 108 causes the pressure rod 165 to move downwards/forwards while guided by the pin 166 in the track 143. This causes the support link 109 to swing forwardly around the pivot pin 192 which, at the same time, slides downwards/forwards in the track 144, where- by the tongue 191 is caused to move forwards along a generally linear path, and in under the transportation object resting on the tongue 148 on one side.

The lever 105 is returned in a direction towards the horizontal plane, partly as a result of the effect of the weight of the transportation object and partly by the action of the pull spring 122, and takes the posi¬ tion shown in chain lines in Figure 7 and therewith causes the pressure rod 154, with the guide pin 155, to pass the pressure spring 163 mounted in the track 162 and also a vertical line which passes through the pivot pin 108.

The transportation object now rests firmly on the tongues 148, 149, and on the tongue 191 in particular. The lever 105 and the pressure rod 154 are located in positions from which they can act to load the object on the cart and to return the arrangement to its rest position, which is effected in the following manner:

The lever 105 is caused to swing around the pivot pin

107 with pressure applied to the pedal 151, whereby the tongue 148 will lift the object in the aforedescribed manner.

The pressure rod 154 places the rocker arm 106 in the position illustrated in Figure 6 while engaging the rear vertical part of the track 162.

The pressure rod 165 is returned by the pulling action of the rocker arm 106 to the position shown in Figure 6 while the pin 166 is guided in the track 143, whereby the support link 109 swings rearwards and the tongue 191 is returned to its rest position, shown in Figure 6, behind the forward frame tubes of the tubular frame walls 104, 104'; the rotational centre (the pivot pin 192) of the support link 109 therewith slides back to its upper position in the track 144.

The pull spring 122 resets the lever 105 to its gener- ally horizontal rest position, wherein the pivot point

153 takes a lower position on its movement path around the pivot pin 107 and therewith draws the pressure rod

154 downwards in the U-shaped track 162, past the pres¬ sure spring 163 and also past a vertical line which extends through the pivot pin 108; at the same time, the tongue 148 is, of course, lowered to the ground with the load resting on the tongue, and the cart is backed-off from the load.

The arrangement 100 is now again in the stable rest position, from which it can again be used to lift and transport further loads, or objects, by repeating the aforedescribed steps.

The invention has been described in the aforegoing with reference to an exemplifying embodiment thereof and also

with reference to the accompanying drawings. The draw¬ ings are purely schematic and do not show the exact geometry of the arrangement in all respects, but are only intended to provide an understanding of the invention.

Although the arrangement of the exemplifying embodiment is manoeuvered manually, it will be understood that it can be equipped advantageously with hydraulic means for switching between the rest and working modes of the cart, for instance by providing a hydraulic piston which acts on the rocker-arm lever.

The invention achieves the aforesaid object of providing a cart which can be used equally as well to lift and transport loads from the same supporting surface as that on which the cart stands and to lift and transport loads from pallets and corresponding raised surfaces.

A person skilled in this art will realize that the inventive cart can be modified structurally in different ways and that such modifications will lie within the scope of the invention as defined in the following Claims.