Counterbalance forklift with driver protection roof

Abstract

A counterbalanced forklift truck with a tiltable mast (12), a counterweight (4), and at least one fixed vertical support (13, 14) arranged on the counterweight (4) in the longitudinal direction of the vehicle behind a driver's workstation (22), wherein the mast (12) is connected to the vertical support (13, 14) via at least one tilting cylinder (15, 16), and a driver's overhead guard (20) is pivotally coupled to the mast (12) and guided on the vertical support (13, 14), wherein a continuous viewing opening is formed between the driver's workstation (22) in the direction towards the mast (12) and in the direction to the side of the mast (12), characterized in that a front plate (23) in front of the driver's workstation (22) projects at least in a central area (24) only to the extent that protection for a footwell (21) is provided and that the feet standing on a floor plate are prevented from slipping into the area of ​​the Lifting mast (12) is not possible,wherein the end plate (23) has at least one handle (25, 26) on each side.

Description

[0001] The present invention relates to a counterbalance forklift truck with a tiltable lifting mast, a counterweight, and an overhead guard articulated to the lifting mast. In particular, the present invention relates to a forklift truck with a tiltable lifting mast, a counterweight, and at least one fixed vertical support arranged on the counterweight behind a driver's workplace in the vehicle's longitudinal direction. The lifting mast is connected to the vertical support via at least one tilt cylinder, and an overhead guard articulated to the lifting mast and guided on the vertical support. A continuous viewing opening is formed between the driver's workplace toward the lifting mast and to the side of the lifting mast.

[0002] It is known to provide a driver's protective roof above the driver's workplace of an industrial truck, in particular a forklift truck, which has a lifting mast and can use this to lift loads to sometimes considerable heights, as protection against falling objects.

[0003] In known solutions for an overhead guard, two pillars are usually arranged in front of the driver's workplace, spaced apart from each other in the transverse direction of the vehicle, serving as A-pillars. These pillars, together with B-pillars arranged behind the driver's seat and also spaced apart in the transverse direction of the vehicle, support the overhead guard above the driver's workplace. Other known designs include the overhead guard, which, as an alternative to a sufficiently thin-mesh grille, is made partially or entirely of a transparent material, particularly a laminated glass pane, so that the upward view is restricted as little as possible.

[0004] In the footwell area of ​​the driver's workplace on known forklift trucks with a lifting mast, a firewall is arranged in front of this footwell. This firewall usually consists of a substantially vertically arranged sheet of metal and prevents a foot placed on a floor or floor plate of the footwell from moving forward out of the footwell area and into the danger zone of the lifting mast arranged in front of this footwell. In state-of-the-art forklift trucks, a dashboard is usually arranged on top of this firewall in front of the driver's workplace, on which display devices and / or control devices for the forklift truck's functions are provided. A steering device, usually in the form of a steering wheel, is integrated into this dashboard or on a separate steering column arranged on the floor plate and arranged in front of the dashboard in the direction of the driver's seat.There is usually a windshield in front of the dashboard.

[0005] A disadvantage of this state-of-the-art technology is that the A-pillars further restrict the view of a driver in the driver's seat at the driver's workstation. In particular, at certain angles, the field of vision can be largely obscured if the areas of vision covered by the A-pillars or parts of the lifting mast are adjacent to each other. However, the most unobstructed view possible of any load or, for example, storage locations in shelves at different heights is crucial for the safe operation of a forklift truck and a prerequisite for driving purposefully to a storage location without causing damage, for example, by bumping into the shelf.

[0006] For the same reasons, the driver's line of sight from the driver's seat, straight down in front of the driver's workstation, is particularly important, as this is the position of the forks when picking up a load from the ground. However, since the dashboard and bulkhead have a certain height, this straight line of sight is obscured, and a view of the forks or the backs of the forks when the load is fully lowered is either impossible or only possible if an operator rises from the driver's seat and leans forward.

[0007] It is also known that the tilt cylinders required for a tilting mast are not located in the lower section of the mast, but rather are coupled to the mast at the height of the overhead guard and connected to two vertical supports spaced apart in the transverse direction of the vehicle behind the driver's workplace, which can be identical to the B-pillars of the overhead guard. It is also known that the actual overhead guard is designed as a movable lattice or ladder frame that is hinged to the mast and guided between the vertical supports so that it can be moved in the longitudinal direction of the vehicle.

[0008] A disadvantage of this prior art design, as with the previously described overhead guard, is that the view upwards is restricted if the load is raised very high on the mast.

[0009] US 2,810,489 A shows a forklift with a tilting mast mounted at the front end of a vehicle body, the forklift having a counterweight. A driver guard comprises a pair of flexible metal strips, one end of which is pivotally connected to the upper portion of the mast and the other end of which is pivotally connected to the counterweight, as well as connecting elements between these metal strips that extend over the driver's position.

[0010] The disadvantage of this state-of-the-art design is that it also restricts upward visibility and doesn't offer the option of mounting the tilt cylinders at a higher position, which would result in more favorable torque. Furthermore, a relatively high bulkhead and a steering wheel and column positioned in front of the driver's cab impair visibility of the load forks in the lowered position.

[0011] From US 2 263 981 A a forklift truck is known which has a tiltable lifting mast and in which a driver's protective roof is arranged above the driver's workplace, which is rotatably mounted on the lifting mast and is also rotatably mounted at its rear end on B-pillars, which in turn are rotatably supported on the counterweight of the forklift truck.

[0012] Here, too, it is disadvantageous that there is no possibility of arranging the tilt cylinders at the height of the driver's overhead guard in order to achieve favourable force moments.

[0013] In one illustrated embodiment, US Pat. No. 2,263,981 A shows a driver's workstation with a footwell that is completely open to the lift mast located in front of it. A steering column with a steering wheel is located directly in front of the driver.

[0014] The disadvantage of this state of the art is that, on the one hand, the steering column and the steering wheel obstruct the direct view of the load forks when the load is fully lowered and, on the other hand, there is a risk that, particularly in the case of tall people, the feet in the footwell may come too far forward and into the area of ​​the lifting mast.

[0015] DE 10 2007 059 065 A1, which represents subsequently published prior art, discloses a forklift truck with a tiltable lifting mast and an overhead guard articulated to the lifting mast, which is arranged above a driver's workstation and serves as a torsion support. Behind the driver's workstation, two frame-mounted vertical supports are provided, spaced apart from each other in the transverse direction of the vehicle, on which the overhead guard is guided for longitudinal movement. To enable torsion support of the overhead guard, the vertical supports are each provided with a guide rail at their upper ends, which engages with the rear end of the overhead guard.

[0016] In the embodiment disclosed in this document, a driver's cab consisting of A-pillars is arranged below the overhead guard. The upper ends of the A-pillars are connected to the vertical supports behind the driver's workplace via a cab roof. This ensures that even small objects that could fall through the overhead guard, which is designed as a grid, are caught on the cab roof, which acts as a second overhead guard. A bulkhead is extended relatively high between the two A-pillars and is equipped with a dashboard. A steering wheel with a steering column is also arranged in this area.

[0017] This state of the art therefore also has the features described above, which lead to visual impairments.

[0018] A generic counterbalance forklift truck with the features of the preamble of patent claim 1 is known from Fig.4 of DE 40 16 497 A1 known.

[0019] DE 10 2007 008 280 A1 discloses a forklift truck with a telescopic protective roof.

[0020] US 5 167 481 A discloses a counterbalance forklift truck with a longitudinally adjustable driver's guard, which is supported on frame-fixed vertical supports and is connected to the tiltable lifting mast.

[0021] JP H10 - 36 093 A discloses a counterbalance forklift truck with an overhead guard frame to which a transparent cover can be attached as weather protection.

[0022] US 2007 / 0 074 923 A1 discloses an industrial truck designed as a vertical order picker with a liftable driver's platform on which a lifting mast with a load fork is arranged.

[0023] DE 197 28 312 C1 discloses a counterbalance forklift truck with a driver's cab in which a pivoting driver's seat unit is arranged.

[0024] It is therefore an object of the present invention to provide a forklift truck with a driver's protective roof in which visibility is improved and at the same time the driver's workplace is protected against falling loads.

[0025] This object is achieved in the vehicle's longitudinal direction by a forklift truck having the features of independent patent claim 1. Advantageous further developments are specified in the subclaims.

[0026] The problem is solved by a counterbalance forklift truck having a tiltable lifting mast, a counterweight, and at least one fixed vertical support arranged on the counterweight behind a driver's workplace, the lifting mast being connected to the vertical support via at least one tilt cylinder, and an overhead guard being articulated to the lifting mast and guided on the vertical support. A continuous viewing opening is arranged between the driver's workplace in the direction of the lifting mast and in the direction to the side of the lifting mast. An end plate protrudes in front of the driver's workplace, at least in a central area, only far enough to protect the footwell and to prevent feet standing on a floor plate from slipping into the area of ​​the lifting mast. The end plate has at least one handle on each side.

[0027] Advantageously, this means that the view of a driver, for example, sitting in a driver's seat at the driver's workstation, is not obstructed except by the lifting mast. There are no longer any obstructive elements in the driver's field of vision in front of the driver's workstation in the direction of the lifting mast, particularly in all possible lines of sight from a driver's seated position. In particular, the solution according to the invention eliminates the need for an A-pillar. Rather, depending on the relative position of the driver's seat to the vertical supports, an unobstructed horizontal field of vision of approximately 180° forward is available.

[0028] Furthermore, the design significantly simplifies and reduces the number of components, as the already familiar structure, which serves as a torsion support and also provides protection against heavy and / or large falling objects, simultaneously assumes many of the functions of the overhead guard and any cab roof, such as weather protection. This eliminates the need to provide a cab roof with A-pillars and the associated additional components, as well as the need to integrate the A-pillar into the vehicle structure and body. Furthermore, boarding and access to the driver's workplace are simplified, as a maximum-sized opening is provided.

[0029] According to the invention, the front plate in front of the driver's workplace, at least in the central area, only protrudes far enough to provide protection for the footwell, so that feet standing on a floor plate cannot slip into the area of ​​the lifting mast.

[0030] Since the front plate in this embodiment of the invention does not have a windscreen, it can be pulled down very low, allowing a direct line of sight from the normal seating position of a driver on a driver's seat in the driver's workstation to the backs of the forks or the tips of the forks in the fully lowered position of a load fork on the lift mast. The front plate can only be designed to extend far enough to generally rule out reaching over it into the danger zone of the lift mast, even with a slightly raised foot. This is the case when a height is taken into account that can usually only be exceeded by deliberately raising the feet, approximately in the order of 10-20 cm.

[0031] According to the invention, the front plate has at least one handle on each side.

[0032] This allows a handle to be positioned conveniently on one or both sides of the vehicle, providing a way to hold on or pull yourself up when entering the driver's seat and entering the vehicle. In particular, such a handle replaces the option of holding on to the A-pillar, which is missing here.

[0033] In an advantageous embodiment, two vertical supports are arranged at a distance from each other in the transverse direction of the vehicle, each with a tilt cylinder.

[0034] This allows for optimal and torsionally rigid support of the mast. In particular, torsional vibrations around the vertical axis of the mast can be effectively absorbed, and the torque required for tilt support can be efficiently transferred to the mast.

[0035] Furthermore, the overhead guard can be guided on both sides in the area of ​​the vertical supports, thus providing more rigid and firm support for the overhead guard.

[0036] The driver's protective roof can be connected to the lifting mast by means of an articulation and can be guided so that it can be moved longitudinally between the tilt cylinders.

[0037] This means that the actual overhead guard is always located directly next to the mast, eliminating any gaps between the mast and overhead guard through which objects could fall. With a sufficiently long overhead guard in relation to the vehicle's longitudinal direction, the driver's workstation is always completely covered by the overhead guard.

[0038] In an advantageous embodiment, the driver's protective roof is guided laterally and / or vertically on the tilt cylinders and / or vertical supports.

[0039] By providing lateral support for the overhead guard, a corresponding force can be transferred to the vertical supports in the event of a transverse movement of the overhead guard. The overhead guard, which is connected to the lifting mast, supports the lifting mast against lateral displacement or torsional moments around the vertical axis of the lifting mast. The horizontal transverse forces at the end of the overhead guard resulting from such torsional rotations of the lifting mast around the vertical axis are supported by the vertical supports, preventing torsion. The overhead guard thus acts as a torsion support.

[0040] In a favorable embodiment, the overhead guard comprises a transparent material, in particular a transparent plastic or a glass pane, in particular a laminated glass pane made of safety glass. The transparent material of the overhead guard can be arranged within a frame. In particular, this frame can be a metal frame. For example, it is possible for a transparent plastic pane or a laminated glass to be elastically mounted in such a metal frame, which is sufficiently rigid in itself, or alternatively to be firmly glued. Both designs ensure that either the rigid metal frame can transmit high transverse forces and, in addition to the function of the overhead guard, can also assume the function of a torsion support, or that in the case of a glued laminated glass pane, the glass pane also absorbs transverse forces.

[0041] Such a transparent overhead guard only minimally restricts upward visibility. Nevertheless, all safety requirements against falling objects can be met with appropriate design of the plastic or laminated glass pane. Since the laminated glass pane must be designed to be sufficiently strong and resilient to ensure puncture resistance, if it is bonded to a frame and this frame is supported on the vertical supports in a transverse direction of the vehicle, it can also support the considerable torsional forces of the lifting mast, while the overhead guard simultaneously acts as a torsional support. This leads to weight savings and simplifies the structure.

[0042] Furthermore, the front plate can extend further upwards in the area of ​​the handles than in the middle area.

[0043] In an advantageous embodiment, control devices for the forklift are arranged on one or two armrests located on a driver's seat. One control device may consist of a steering device located in a left armrest. This steering device may optionally be designed as a very small rotary wheel, which may alternatively also have a rotary knob for easier operation with one hand or with a few fingers of one hand.

[0044] In an advantageous embodiment, control levers for raising / lowering a lifting device of the lifting mast and / or control levers for the travel control and / or travel direction switch can be arranged in a right-hand armrest.

[0045] This advantageously avoids the need to position a steering column with a steering wheel in front of the driver's seat in the driver's work area, which would otherwise create an obstacle in the line of sight to the forks or the back of the forks when the lifting device's forks are in their lowest position. Furthermore, by arranging the controls in the two armrests using small control levers, particularly joysticks, it is possible to avoid the need for controls in the dashboard area, thus eliminating the need for a dashboard.

[0046] Additionally, it is possible to arrange display devices, especially displays, in the armrests. Alternatively, it is also conceivable to mount such display devices, if necessary, on the rear of the lifting mast, possibly on special brackets. Another alternative is to attach them to the overhead guard or one of the tilt cylinders on the underside, or to suspend them using a suitable mounting device.

[0047] Further advantages and details of the invention are explained in more detail with reference to the embodiment shown in the schematic figure. Figure is a perspective overall view of a forklift truck according to the invention.

[0048] The forklift truck shown in the figure has a frame 1 on which a front axle 2 and a rear axle 3 are arranged. A counterweight 4 is located above the rear axle 3. In front of the counterweight 4 is a driver's seat 5, which has a steering device 7 in the form of a small disc with an attached rotary knob 8 on a left armrest 6, so that the steering device 7 can be operated using only a movement of the left hand or a few fingers. On a right armrest 9, further control levers 10 in the form of joysticks are provided, with which the raising and lowering of a load-handling device in the form of a load fork 11, which is arranged on a lifting mast 12, as well as the tilting of the lifting mast 12 and any additional drives present, for example a side shift of the load fork 11, can be controlled. The right armrest 9 contains a travel direction switch, and driving and braking are controlled via pedals.Alternatively, the driving / braking of the forklift truck can also be controlled via the control levers 10.

[0049] A left fixed vertical support 13 and a right fixed vertical support 14 are arranged on the counterweight 4, relative to the direction of travel of the forklift. A left tilt cylinder 15 and a right tilt cylinder 16 are each hinged to the left vertical support 13 and the right vertical support 14 and to the lifting mast 12 and can tilt the lifting mast 12. A cross brace 17 connects the left vertical support 13 and the right vertical support 14 in the upper area and provides greater rigidity against lateral forces relative to the vehicle's longitudinal axis.

[0050] A laminated glass pane 18 is inserted into a frame 19 and the frame 19 is movably connected to the lifting mast 12 and is vertically guided in the upper end regions of the left vertical support 13 and right vertical support 14, for example by support rollers or sliding pieces, so that the laminated glass pane 18 and the frame 19 together form a driver protection roof 20.

[0051] If the overhead guard 20 is additionally guided laterally on the vertical supports 13, 14 by means of corresponding horizontal support rollers or sliding pieces, the overhead guard 20 can additionally support the torsional movements of the lifting mast 12 about a vertical axis and stiffen the lifting mast 12. At the same time, the overhead guard 20 covers the area of ​​the driver's seat 5, which, together with a footwell 21, forms a driver's workstation 22.

[0052] The footwell 21 is delimited at its front by an end plate 23, which in a central region 24 only protrudes far enough that feet would strike it if moved forward, thus preventing them from entering the danger zone of the lifting mast 12. The lowered end plate 23 in the central region 24 enables a view of a fork carriage, which is guided on the lifting mast 12 and carries the load forks 11, in the fully lowered position. The end plate 23 is extended upwards at the side edges of the vehicle and has a left handle 25 and a right handle 26. In the area of ​​the left handle 25 and the right handle 26, the end plate 23 thus extends further upwards than in the central region 24. Together with a step 27, the left handle 25, for example, enables comfortable access to the driver's workplace 22.

[0053] The embodiment of a forklift truck according to the invention shown in the figure has a continuous viewing opening in the direction of the lifting mast 12 and to the side of the lifting mast 12. Since, in the present exemplary embodiment, the left vertical support 13 and the right vertical support 14 are arranged behind the driver's seat 5, this results in a clear all-round view of more than 180° in the direction of the lifting mast 12, without any interfering structural elements, in particular an A-pillar of a conventional cab roof, obstructing the view. In particular, there can be no combination or overlap of obscured viewing areas consisting of elements of the lifting mast 12 and an additional A-pillar.

[0054] Irrespective of this, the forklift truck according to the invention has the advantage that the transparent laminated glass pane 18, with appropriate dimensions, provides sufficient protection against falling objects when the load fork 11 has been raised fully on the lifting mast 12. In particular, there is no gap between the lifting mast 12 and the overhead guard 20, since the overhead guard 20 is rotatably attached to the lifting mast 12 and thus always connects directly to the lifting mast 12. During a tilting movement, the tilt cylinders 15, 16 are moved along with it and always cover the area above the driver's workplace 22. The overhead guard 20 can simultaneously fulfill the function of a torsion support for the lifting mast 12 and does not obstruct the view upwards, since there is only one transparent element, here the laminated glass pane 18, in the central axis directly above the driver.

[0055] Also independent of this is the advantage that the driver's line of sight from the driver's seat 5 to the load forks 11 is not obstructed by the front plate 23 in its central region 24, yet comfortable operation of the forklift is still possible, since the steering device 7 is arranged in the left armrest 6 and additional control devices in the form of control levers 10 are arranged in the right armrest 9, thus eliminating the obstructive steering column with a steering device or other control elements in the driver's line of sight. Nevertheless, the sufficiently raised central region 24 of the front plate 23 ensures that feet cannot slip from the footwell 21 into the danger zone of the lifting mast 12.

Claims

[1] Counterbalance forklift truck with a tiltable lifting mast (12), with a counterweight (4) and at least one fixed vertical support (13, 14) arranged on the counterweight (4) behind a driver's workplace (22) in the vehicle's longitudinal direction, wherein the lifting mast (12) is connected to the vertical support (13, 14) via at least one tilt cylinder (15, 16) and a driver's protective roof (20) is articulatedly coupled to the lifting mast (12) and is guided on the vertical support (13, 14), wherein a continuous viewing opening is formed between the driver's workplace (22) in the direction of the lifting mast (12) and in the direction to the side of the lifting mast (12), characterized bythat a front plate (23) in front of the driver's workplace (22) at least in a central region (24) only protrudes to such an extent that protection for a footwell (21) is provided and slipping of feet standing on a floor plate into the area of ​​the lifting mast (12) is not possible, wherein the front plate (23) has at least one handle (25, 26) on each side. [2] Counterbalance forklift truck according to claim 1, characterized by that two vertical supports (13,14) are arranged spaced apart from one another in the transverse direction of the vehicle, each with a tilt cylinder (15,16). [3] Counterbalance forklift truck according to claim 2, characterized by that the driver's protective roof (20) is connected to the lifting mast (12) and is guided so as to be displaceable in the longitudinal direction between the tilting cylinders (15, 16). [4] Counterbalance forklift truck according to claim 3, characterized by that the driver's protective roof (20) is guided laterally on the tilt cylinders (15, 16) and / or vertical supports (13,14). [5] Counterbalance forklift truck according to one of the preceding claims, characterized by that the driver's protective roof (20) comprises a transparent material, in particular a transparent plastic or a glass pane, in particular a laminated glass pane (18). [6] Counterbalance forklift truck according to claim 5, characterized by that the driver's protective roof (20) has the transparent material within a frame (19), in particular a metal frame. [7] Counterbalance forklift truck according to one of claims 1 to 6, characterized by that the front plate (23) extends further upwards in the area of ​​the handles (25,26) than in the middle area (24). [8] Counterbalance forklift truck according to one of claims 1 to 7, characterized by that control devices for the forklift truck are arranged on one or two armrests (6,9) of a driver's seat (5). [9] Counterbalance forklift truck according to claim 8, characterized bythat the control device is a steering device (7), in particular a steering wheel with a rotary knob (8), arranged in a left armrest (6). [10] Counterbalance forklift truck according to claim 8 or 9, characterized by that control levers (10) for raising / lowering a lifting device of the lifting mast (12) and / or control levers (10) or travel direction switches for the travel control are arranged in a right armrest (9).

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