forklift

Abstract

The subject matter of the invention is open top walk behind forklift with electro-hydraulic drive system capable of being transported by suspending the forks (6) on the body (10) of a transport vehicle, consisting of: U-shaped welded skeletal support frame (1) made of steel profiles and plates, a chassis system including two front wheels (2) and torsional twin rear wheels (3), with front wheels (2) driven by hydraulic motors attached to the support frame (1) by hubs, electro-hydraulic drive system, a power- assisted steering system located in the central upper part of the support frame (1) of the forklift above the steering wheel, including a steering column (7) and a multifunction steering wheel (8) for controlling the forklift, a platform (9) for the operator located in the center rear lower part of the forklift for higher-speed driving, mast (4) with carriage (5) located centrally on the support frame (1) between the front wheel supports (2), telescopic forks (6) mounted on a carriage (5), the telescopic forks (6) being adapted for mounting to an adapter (14) on a transport vehicle, battery, wherein the steering column (7) is capable of pivoting in the vertical plane from the manual guidance position to the higher- speed driving position, and wherein the forklift includes extendable front supports (13) synchronized with the movement of telescoping forks (6).

Description

[0001] FORKLIFT

[0002] The subject of the invention is an open-top-walk-behind forklift with an electro-hydraulic drive system.

[0003] Various forklifts are known in the world of technology. Typically, there are heavy-duty and lighter cabin forklifts for transporting heavy goods both indoors and outdoors. Lighter open-top-walk-behind forklifts with a platform are also known, but typically they have small wheels and are intended to be used on flat surfaces of warehouse halls. They lack the ability to go over bumps and have no drawbar assisting turning. Most often they have a single-wheel drive, low stability when turning with their mast in extended position.

[0004] Transporting forklifts to the place where they need to be used is of paramount imortnce. Heavy cabin forklifts, although they have off-road wheels, would require a transport truck with a GVW of 15 tons or more. Then there is a problem of getting such a forklift to places where such a transport truck cannot enter. Therefore, there is a need for a lightweight open-top-walk-behind forklift, which will eliminate these disadvantages of traditional forklifts.

[0005] Also known in the patent literature are designs for bodies of transport vehicles carrying forklifts. For example, a body with channels for forklift forks is included in document number P.439185. The channels have locking systems attached to the body of the transport vehicle. The channels for forklift forks are in the form of elongated rectangular pockets.

[0006] The purpose of developing the forklift according to the invention is to provide more comfortable steering for the operator. Thanks to the specially designed steering column, the operator does not need to "lean out" when turning beyond the forklift's path as it is the case with a conventional drawbar. Such a rotary drawbar is known on the market, however, in addition to the vertical movement, the operator also needs to make lateral movement using muscle force. This requires an arm (drawbar) and this one causes a significant obstacle in tight working corridors where the operator has to lean significantly out of the forklift's path when making a turn.

[0007] In addition, this innovation solves the problem of a difficult approach to the goods the forklift is supposed to pick up and transport. The forklift has telescopic extending forks that can slide under the goods when the front wheels encounter an obstacle (e.g., when the goods are being taken up from the centre of the vehicle's loading platform). Also, there are extendable front supports synchronized with the movement of telescoping forks. They provide stabilization for the truck, for which the centre of gravity shifts forward significantly when the goods are lifted on the retracted forks. The object described here as invention herein is an open-top-walk-behind forklift with electro-hydraulic drive system capable of being transported by locking the forks (6) on the transport vehicle body (10), consisting of:

[0008] - U-shaped welded support frame made of steel profiles and plates,

[0009] - A chassis system including two front wheels and torsional twin rear wheels, with front wheels driven by hydraulic motors attached to the support frame by hubs,

[0010] - electro-hydraulicdrive system,

[0011] - A power-assisted steering system located in the central upper part of the support frame of the forklift above the steering wheel, including a steering column and a multifunction steering wheel for controlling the forklift,

[0012] - A platform for the operator located in the centre rear lower part of the forklift for higher-speed driving,

[0013] - Mast with carriage located centrally on the support frame between the front wheel supports,

[0014] - telescopic forks mounted on a carriage, the telescopic forks being adapted for mounting to an adapter on a transport vehicle,

[0015] - battery, unique in that the steering column is capable of pivoting in the vertical plane from the manual guidance position to the higher-speed driving position, and in the fact that the forklift includes extendable front supports synchronized with the movement of telescoping forks.

[0016] Advantageously, the forklift running system includes an ASR system to prevent wheel slip. Advantageously, the battery is made as a lithium-ion battery.

[0017] The forklift is advantageously equipped with an electrical socket for connecting lights and for recharging batteries from a car-mounted generator.

[0018] The truck is advantageously equipped with rear taillights.

[0019] SUBSTITUTE SHEET (RULE 26) Advantageously, the forklift is equipped with covers to protect the forklift equipment components from mechanical damage and contamination.

[0020] Advantageously, the forklift also includes chain bolts mounted on the support frame for anchoring and securing the forklift suspended from the body of the transport vehicle.

[0021] The forklift according to the invention is shown in the figure, in which:

[0022] Fig. 1 shows a side view of the forklift according to the invention;

[0023] Fig. 2 shows the suspension of the forklift according to the invention on the body of the car transporting it.

[0024] The forklift according to the invention is shown in Fig. 1. It has a "U" shaped space frame (1) made of profiles and properly shaped steel sheets joined by laser welding. 2 front wheels (2) and the torsional twin rear wheels (3) are attached via hubs and hydraulic motors to the space frame. In the central part of the forklift, between the supports of the front wheels (2) there is a mast (4) with a carriage (5) and telescopic forks (6) fitted - in the variant of the forklift for suspension under a transport car - to an adapter 14 mounted on the car is mounted.

[0025] In the central upper part of the truck's space frame (1), above the steering wheel, is mounted a power steering system consisting of a movable steering column (7) and a multifunctional steering wheel (8) having all the functions of controlling the truck's driving and operational functions.

[0026] In the centre rear lower part of the forklift there is a platform (9) for the operator, allowing faster movement if needed. The operator's platform (9) can be folded down if the operator is driving the forklift - then the forklift operates in "turtle" mode and travels at speeds of up to 6 km / h. If needed to drive faster to the object, the platform can be unfolded and the operator can stand on it - then the forklift can work in a "hare" mode providing faster driving; 6-18 km / h.

[0027] The interior of the spatial frame is filled with all the necessary mechanisms needed to ensure proper operation of the forklift. Unless otherwise specified they are typical, meaning they are typically connected and have standard functions.

[0028] The truck according to the invention contains lithium-ion batteries, main electric motor, main hydraulic motor (pump), function control sections, hydraulic tank, steering cylinder, control computer, sensors.

[0029] The battery can be recharged from a power outlet or from a transport vehicle's generator while it is in motion. From the outside, the forklift is encased in covers that protect the above-mentioned elements from mechanical damage and contamination.

[0030] The forklift according to the invention has off-road wheels. The wide spacing of the front wheels (2) allows turning on uneven terrain with the mast (4) raised. The front wheels (2) driven by hydraulic motors are attached to the support frame (1) by hubs.

[0031] The forklift according to the invention can be adapted for suspension on the body (10) of trucks and vans.

[0032] Chain bolts (11) anchoring and securing the forklift under the car for transport are attached to the supporting structure of the forklift providing the possibility of suspension on the body of the transport car.

[0033] The forklift also has a current socket (12) for connecting lights and for charging batteries from a carmounted generator.

[0034] The forklift according to the invention has an electro-hydraulic all-wheel drive. Power transmitted to the wheel drive motors is obtained via a main hydraulic pump powered by an electric motor. The forklift is also provided with an ASR system to prevent wheel slippage.

[0035] The forklift according to the invention has a power steering system (8) that allows to manoeuvre freely, especially in muddy surfaces. In addition, the forklift has a movable steering column (7), moving only in the vertical axis, so that the operator does not have to "lean out" when turning beyond the forklift's travel light, i.e. beyond the outline of the forklift. The movable steering column (7) makes it possible to optimize the angle of inclination and the distance of the operator from the forklift, depending on whether the operator is driving the forklift (up to 6km / h) or driving it using the folding platform (6- 18kmh).

[0036] The traditional swivel drawbar in known trucks required, in addition to movement in the vertical axis, a side-to-side motion when turning. Turning by muscle force requires an arm (drawbar), and this causes a significant obstacle in tight working corridors where, when turning, the operator, using the drawbar, has to lean significantly out of the travel light. This did not benefit the operator in tight work corridors. The steering column (7) of the forklift according to the invention eliminates this problem. When the operator is driving the forklift the steering column (7) is lowered i.e. in the "down" position, giving an increased distance between the operator and the forklift. THE operator following the forklift in walking mode must maintain a certain distance to allow free stepping. Also, when reversing, an adequate distance between the operator and the forklift protects the operator'sfoot with the turning wheel, this distance must be maintained for safety reasons. When the operator stands on the platform (9) the steering column (7) is in the "up" position, which gives a reduced distance between the operator and the forklift. In this case, when the platform on which the operator stands is unfolded, the distance between the forklift and the operator is corrected to a minimum, as there is no danger of stepping on the foot and no obstruction to stepping in driving mode. The steering column (7) moves in the vertical plane.

[0037] The forks (6) extend telescopically. This allows the extended forks (6) to pick up the goods without having to drive the forklift up. This is especially advantageous when the forklift cannot go under the goods due to congestion of goods or narrow passage. In order to balance the weight of the goods on the long arm with the telescopically extended forks (6), the forklift according to the invention is provided with extendable front supports (13) synchronized with the movement of the telescopically extended forks (6). The front supports (13) stabilize the vehicle during the lifting of the goods. Thanks to this solution, stability and lifting capacity are significantly improved when the centre of gravity is shifted forward. Such a solution makes it possible to stably and safely pick up a load that is far away from the loading edge of the vehicle and prevents torsional axle strain.

[0038] The forklift has an electro-hydraulic drive to all wheels - this gives high torque and improves traction, advantageously through the presence of ASR Anti-Slip Regulation to prevent wheel slippage. Hydraulic motors also provide a life advantage in the harsh terrain and weather conditions for which the forklift according to the invention is intended.

[0039] The forklift weighs about 800 kg and can carry and transport a weight of 1000-1200 kg in heavy terrain. Thus, the low total weight of the forklift and the goods is ensured, the relatively low unit pressure of the wheels allows to move in terrain where heavier forklift may bog down (in sand, mud, grass, snow).

[0040] Thanks to the electro-hydraulic power supply, the forklift, which has all the qualities of an off-roader, can also move indoors where the poor quality of the floors disqualifies an ordinary "electric pallet truck".

[0041] For the variant of the forklift that provides the ability to be suspended on the body (10) of a transport truck, space is also provided for the taillights and license plate. When transporting the forklift on the body (10) of a truck, all lighting functions of the truck are covered by the forklift, and then it is the forklift that must have them. The Orderer's forklift can be transported, due to its low weight, by trucks weighing 3.5-7.5 t making it transportable between loading and unloading locations. Any such truck can be adapted to suspend the forklift according to the invention.

[0042] The adapter (14) shown in Fig. 2. It consists of two fork slots permanently attached to the car chassis and the method of attaching the truck to the car is to slide the forks (6) into the slots, suspend the truck to the required height and secure it with additional chain bolts (11). The body (10) according to this adaptation advantageously includes additional slots for the front axle supports of the bogie.

[0043] The transport car is equipped with a generator to recharge the truck, making it zero-emission. Since charging takes place while the car has the engine running, no additional energy is lost to power the charger from the mains socket. The advantage of such a solution, in addition to energy savings, is also an important practical issue when the operator for example forgets to recharge the batteries from the mains and has a long enough distance to drive is able to recharge the truck during the journey.

Claims

Claims1. Open top walk behind forklift with electro-hydraulic drive system capable of being transported by suspending the forks (6) on the body (10) of a transport vehicle, consisting of:- U-shaped welded skeletal support frame (1) made of steel profiles and plates,- a chassis system including two front wheels (2) and torsional twin rear wheels (3), with front wheels (2) driven by hydraulic motors attached to the support frame (1) by hubs,- electro-hydraulic drive system,- a power-assisted steering system located in the central upper part of the support frame (1) of the forklift above the steering wheel, including a steering column (7) and a multifunction steering wheel (8) for controlling the forklift,- a platform (9) for the operator located in the center rear lower part of the forklift for higher- speed driving,- Mast (4) with carriage (5) located centrally on the support frame (1) between the front wheel supports (2),- telescopic forks (6) mounted on a carriage (5), the telescopic forks (6) being adapted for mounting to an adapter (14) on a transport vehicle,- battery, characterised in that the steering column (7) is capable of pivoting in the vertical plane from the manual guidance position to the higher-speed driving position, and the fact that the forklift includes extendable front supports (13) synchronized with the movement of telescoping forks (6).

2. The forklift according to claim 1, characterised in that the running system includes an ASR system to prevent wheel slip.

3. The forklift according to claims 1 or 2, characterised in that the fact that the battery is made as a lithium-ion battery.

4. The forklift according to claims 1 to 3, characterised in that it is equipped with an electrical socket (12) for connecting lights and for recharging batteries from a generator mounted in the vehicle.

5. The forklift according to claims 1 to 4, characterised in that it is equipped with taillights.

6. The forklift according to claims 1 to 5, characterised in that it is equipped with covers to protect the forklift equipment components from mechanical damage and dirt.

7. The forklift according to claims 1 to 6, characterised in that it includes chain bolts (11) mounted on a support frame (1) for anchoring and securing the forklift when it is mounted on the body of a transport vehicle (10).

Images